The proxy statement/prospectus,statement, including the annexes,Annexes, contains further information with respect to the business to be transacted at the special meeting. We urge you to read the proxy statement/prospectus,statement, including any documents incorporated by reference, and the annexesAnnexes carefully and in their entirety. Tribune will transact no other business at the special meeting, except for business properly brought before the special meeting or any adjournment or postponement thereof. Please refer to the proxy statement/prospectusstatement of which this notice forms a part for further information with respect to the business to be transacted at the special meeting.

BOARD OF DIRECTORS'DIRECTORS’ RECOMMENDATION:

        After careful consideration, theThe board of directors of Tribune Media Company, which we refer to as the "Tribune“Tribune board," on May 7, 2017, approved the merger agreement and determined that the merger agreement and the transactions contemplated thereby are advisable, fair to and in the best interests of Tribune and its shareholders and further resolved that it is recommended to the Tribune shareholders, that they adopt a non-binding, advisory proposal to approve the compensation that may be paid or become payable to Tribune's named executive officers in connection with the merger pursuant to already existing contractual obligations of Tribune.

The Tribune board unanimously recommends that you vote "FOR" each of the merger proposal, the compensation proposal and the adjournment proposal.

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WHO MAY VOTE:

        Only holders of record of Tribune Class A common stock, par value $0.001 per share, which we refer to as the "Tribune Class A common stock," and Tribune Class B common stock, par value $0.001 per share, which we refer to as the "Tribune Class B common stock" and together with the Tribune Class A common stock, the "Tribune common stock," as of the record date, are entitled to receive notice of the special meeting and to vote at the special meeting or any adjournments or postponements thereof. As of the record date, there were 87,282,099 and 5,605 shares of Tribune Class A common stock and Tribune Class B common stock outstanding, respectively. Each share of Tribune common stock is entitled to one vote on the approval of the merger proposal. Holders of Tribune Class A common stock are also entitled to one vote on the approval of the compensation proposal and the adjournment proposal. Holders of Tribune Class B common stock are entitled to vote on only the merger proposal. Tribune shareholders will vote as a single class on the merger proposal. A list of Tribune shareholders of record entitled to vote at the special meeting will be available at the executive offices of Tribune at 435 North Michigan Avenue, Chicago, Illinois 60611 at least ten days prior to the special meeting and will also be available for inspection at the special meeting by any Tribune shareholder for purposes germane to the meeting.

VOTE REQUIRED FOR APPROVAL:

        Your vote is very important. We cannot complete the merger without the approval of the merger proposal. If the merger proposal is not approved by the holders of the requisite number of shares of Tribune common stock, then the transaction will not occur. Assuming a quorum is present, the affirmative vote of a majority of the outstanding shares of Tribune common stock, voting as a single class, entitled to vote on such proposal is required to approve the merger proposal. Approval of each of the compensation proposal and the adjournment proposal require the affirmative vote of at least a majority of the outstanding shares of Tribune Class A common stock present in person or represented by proxy at the special meeting and entitled to vote on such proposals.

        To ensure your representation at the special meeting, please complete and return the enclosed proxy card or submit your proxy by telephone or through the Internet. Please submit your proxy promptly whether or not you expect to attend the special meeting. Submitting a proxy now will not prevent you from being able to vote in person at the special meeting.

		By Order of the Board of Directors,
		Edward P. Lazarus Executive Vice President, General Counsel, Chief Strategy Officer and Corporate Secretary

Chicago, Illinois
September 6, 2017

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REFERENCES TO ADDITIONAL INFORMATION

        Sinclair Broadcast Group, Inc., which we refer to as "Sinclair," has filed a registration statement on Form S-4 to which this proxy statement/prospectus relates. This proxy statement/prospectus does not contain all of the information included in the registration statement or in the exhibits to the registration statement to which the accompanying proxy statement/prospectus relates.

        This proxy statement/prospectus also incorporates by reference important business and financial information about Sinclair and Tribune Media Company, which we refer to as "Tribune" from documents previously filed by Sinclair or Tribune with the SEC, that are not included in or delivered with this proxy statement/prospectus. In addition, Sinclair and Tribune each file annual, quarterly and current reports, proxy statements and other business and financial information with the SEC.

        This proxy statement/prospectus and the Annexes hereto, the registration statement to which this proxy statement/prospectus relates and the exhibits thereto, the information incorporated by reference herein and the other information filed by Sinclair and Tribune with the SEC is available for you to review at the SEC's Public Reference Room located at 100 F Street, N.E., Room 1580, Washington, DC 20549. You can also obtain these documents through the SEC's website at www.sec.gov or on either Sinclair's website at http://www.sbgi.net in the "Investors" section or on Tribune's website at http://www.tribunemedia.com in the "Investors" section. By referring to Sinclair's website, Tribune's website, and the SEC's website, Sinclair and Tribune do not incorporate any such website or its contents into this proxy statement/prospectus.

        This proxy statement/prospectus incorporates important business and financial information about Sinclair and Tribune from other documents that are not included in or delivered with this proxy statement/prospectus. This information is available to you without charge upon your request. You can obtain these documents incorporated by reference into this proxy statement/prospectus by requesting them in writing or by telephone from the appropriate company at the following addresses and telephone numbers:

        See "Incorporation of Certain Documents by Reference" beginning on page 185 for more information about the documents incorporated by reference in this proxy statement/prospectus.

        If you hold your shares in "street name," through a bank, broker or other nominee, you should contact such bank, broker or other nominee if you need to obtain a voting instruction card or have questions on how to vote your shares.

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QUESTIONS AND ANSWERS ABOUT THE TRANSACTION AND THE SPECIAL MEETING

        The following are brief answers to common questions that you may have regarding the merger agreement, the transaction, the consideration to be received in the transaction and the special meeting (as discussed below). The questions and answers in this section may not address all questions that might be important to you as a Tribune shareholder. To better understand these matters, and for a description of the legal terms governing the transaction, we urge you to read carefully and in its entirety this proxy statement/prospectus, including the Annexes to, and the documents incorporated by reference in, this proxy statement/prospectus, as well as the registration statement to which this proxy statement/prospectus relates, including the exhibits to the registration statement. See "Incorporation of Certain Documents by Reference" beginning on page 185 and "Where You Can Find More Information" beginning on page 187.

Q:

What is the transaction?

A:

On May 8, 2017, Sinclair, Tribune and Samson Merger Sub Inc., one of Sinclair's wholly-owned subsidiaries, which we refer to as "Merger Sub," entered into the merger agreement. The merger agreement is attached to this proxy statement/prospectus as Annex A. The merger agreement provides for a merger with Tribune, as a result of which Tribune will be acquired by Sinclair. We sometimes refer to the merger and the other transactions contemplated by the merger agreement, taken as a whole, as the "transaction." The merger will be effective, after all of the conditions to the closing of the transaction are satisfied or, to the extent permitted by law, waived, at the time a certificate of merger is filed with the Secretary of State of the State of Delaware or at such later time and date designated jointly by Sinclair and Tribune in the certificate of merger, which we refer to as the "effective time."

Q:

What will I receive in the merger?

A:

In the merger, each share of Tribune Class A common stock, par value $0.001 per share, and Tribune Class B common stock, par value $0.001 per share, which we refer to as the "Tribune Class A common stock" and the "Tribune Class B common stock" respectively, and together as the "Tribune common stock," issued and outstanding immediately prior to the effective time, will be converted into the right to receive (i) $35.00 in cash, without interest and less any required withholding taxes, which we refer to as the "cash consideration" and (ii) 0.2300 of a share of Sinclair's Class A common stock, par value $0.01 per share, which we refer to as the "Sinclair Class A common stock," and such consideration which we refer to as the "stock consideration." We refer to the cash consideration and the stock consideration together as the "merger consideration." We also refer to the 0.2300 of a share of Sinclair Class A common stock constituting the stock consideration as the "exchange ratio."

No fractional shares of Sinclair Class A common stock will be issued in the merger. Tribune shareholders will receive cash, without interest, in lieu of any fractional shares.

Q:

Why am I receiving this document?

A:

In order to complete the transaction, the Tribune shareholders must vote upon and approve and adopt the merger agreement and the merger at the special meeting. Tribune will hold for this purpose a special meeting of its shareholders, which we refer to as the "special meeting." We are sending you these materials to help you decide how to vote your shares with respect to the matters to be considered at the special meeting. This proxy statement/prospectus contains important information about the transaction and the special meeting. You should read carefully and in its entirety this proxy statement/prospectus, including the Annexes to, and the documents incorporated by reference in, this proxy statement/prospectus, as well as the registration statement to which this proxy statement/prospectus relates, including the exhibits to the registration statement. The

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enclosed proxy or voting instruction cards allow you to authorize the voting of your shares without attending the special meeting.

Your vote is very important. We encourage you to submit a proxy or voting instructions as soon as possible.

Q:

What equity stake will the pre-transaction Tribune shareholders and Sinclair shareholders hold after the closing of the transaction?

A:

The merger will result in the pre-transaction Tribune shareholders owning approximately 16.8% of the outstanding shares of Sinclair common stock and existing Sinclair shareholders owning approximately 83.2% of the outstanding shares of Sinclair common stock immediately following the closing of the transaction. In August 2017, Sinclair repurchased approximately 997,300 shares of Sinclair Class A common stock under its existing share repurchase program. If Sinclair repurchases additional shares of Sinclair Class A common stock prior to the closing of the transaction, the percentages that the pre-transaction Tribune shareholders and Sinclair shareholders will own of Sinclair's common stock immediately following the closing of the transaction will correspondingly adjust. We refer to the Sinclair Class A common stock and Sinclair Class B common stock collectively as the "Sinclair common stock."

Q:

What voting stake will the pre-transaction Tribune shareholders and Sinclair shareholders hold after the closing of the transaction?

A:

After the closing of the transaction, the pre-transaction Tribune shareholders will receive approximately 20.1 million shares of Sinclair Class A common stock. The pre-transaction Tribune shareholders will not receive any shares of Sinclair Class B common stock. David Smith, Frederick Smith, J. Duncan Smith and Robert Smith hold substantially all of the Sinclair Class B common stock and a portion of the Sinclair Class A common stock. Holders of the Sinclair Class A common stock are entitled to one vote per share, and holders of the Sinclair Class B common stock are entitled to ten votes per share, except for votes relating to "going private" and certain other transactions. The holders of Sinclair Class A common stock and Sinclair Class B common stock vote as a single class except as otherwise may be required by Maryland law on all matters presented for a vote. Shares of Sinclair Class B common stock are convertible into Sinclair Class A common stock at the election of the holder and in certain circumstances are automatically converted into shares of Sinclair Class A common stock. For additional information regarding the rights of the holders of the Sinclair Class A common stock and Sinclair Class B common stock, see "Description of Sinclair Capital Stock—Sinclair Class A Common Stock" beginning on page 169 and "Description of Sinclair Capital Stock—Sinclair Class B Common Stock" beginning on page 170.

After the closing of the transaction and assuming there are no conversions prior to such closing of shares of Sinclair Class B common stock into shares of Sinclair Class A common stock, based on the number of shares of Sinclair Class A common stock expected to be issued to the Tribune shareholders in the merger and the number of shares of Sinclair Class A common stock outstanding as of May 8, 2017, the pre-transaction Tribune shareholders will hold shares representing (i) approximately 5.8% of the voting power of the Sinclair Class A common stock and Sinclair Class B common stock in circumstances in which the holders of Sinclair Class B common stock are entitled to ten votes per share and (ii) approximately 16.8% of the voting power of the Sinclair Class A common stock and Sinclair Class B common stock in circumstances in which the holders of the Sinclair Class B common are entitled to one vote per share. In August 2017, Sinclair repurchased approximately 997,300 shares of Sinclair Class A common stock under its existing share repurchase program. If Sinclair repurchases additional shares of Sinclair Class A common stock prior to the closing of the transaction, the percentages that the pre-transaction Tribune

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shareholders and Sinclair shareholders will own of Sinclair's common stock immediately following the closing of the transaction will correspondingly adjust.

Q:

What is the value of the merger consideration?

A:

Based on the closing price of $36.95 per share for the Sinclair Class A common stock on May 5, 2017, the last trading day before the announcement of the execution of the merger agreement, the stock consideration had an implied value of $8.50. Adding this amount to the cash consideration of $35.00 results in an implied value for the merger consideration of $43.50 per share of Tribune common stock. The value of the merger consideration Tribune shareholders will receive on the closing of the transaction will depend in part on the market value of the Sinclair Class A common stock immediately before the transaction is completed. The market value at that time could vary significantly from the closing price for the Sinclair Class A common stock on May 5, 2017. Tribune shareholders are advised to obtain current market quotations for the Sinclair Class A common stock.

Q:

When do you expect the transaction to be completed?

A:

The transaction is expected to close in the fourth quarter of 2017. However, the closing of the transaction is subject to various conditions, including the approval and adoption of the merger agreement and the merger at the special meeting, as well as required approval of the transaction by the Federal Communications Commission, which we refer to as the "FCC" and clearance under the Hart-Scott-Rodino Antitrust Improvements Act of 1976, as amended, which we refer to as the "HSR Act," the listing of the Sinclair Class A common stock to be issued in the merger on the NASDAQ and the absence of certain legal impediments to the consummation of the merger. No assurance can be provided as to when or if the transaction will be completed, and it is possible that factors outside the control of Sinclair and Tribune could result in the transaction being completed at a later time, or not at all. See "The Agreements—Description of the Merger Agreement—Other Covenants and Agreements—Efforts to Consummate the Transaction" beginning on page 144 and "The Agreements—Description of the Merger Agreement—Conditions to the Transaction" beginning on page 150.

Q:

What are the conditions to the completion of the transaction?

A:

In addition to the approval of the merger agreement by the Tribune shareholders, completion of the merger is subject to the satisfaction of a number of other conditions, including certain regulatory approvals. For additional information on the regulatory approvals required to complete the merger, see "Transaction Summary—Regulatory Approvals," beginning on page 118 and "The Agreements—Description of the Merger Agreement—Efforts to Consummate the Transaction," beginning on page 144. For additional information on the conditions to completion of the merger, see "The Agreements—Description of the Merger Agreement—Conditions to the Transaction," beginning on page 150.

Q:

What effects will the merger have on Tribune/Sinclair?

A:

Upon completion of the merger, Merger Sub will be merged with and into Tribune, as a result of which Tribune will become a wholly-owned subsidiary of Sinclair. As a condition to closing, the shares of Sinclair Class A common stock issued in connection with the merger are expected to be approved for listing on the NASDAQ.

Q:

What if I hold Tribune warrants?

A:

In accordance with the terms of the warrants, Sinclair will assume each outstanding warrant to purchase Tribune common stock, which we refer to as the "warrants," and each outstanding

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warrant will thereafter be exercisable, at its current exercise price of $0.001, for the merger consideration in respect of each share of Tribune Class A common stock and/or Tribune Class B common stock subject to the warrant prior to the merger.

Q:

What if I hold Tribune stock options or other equity awards?

A:

Each stock option of Tribune that is outstanding immediately prior to the effective time, whether vested or unvested, will be immediately cancelled and converted into the right to receive, with respect to each share of Tribune common stock underlying each such stock option, a cash payment. Any stock option with an exercise price as of the effective time that is greater than or equal to the per share merger consideration will be immediately cancelled in exchange for no consideration. For more information concerning options and other equity compensation, see "The Agreements—Description of the Merger Agreement—Treatment of Stock Options, Warrants and Other Stock-Based Awards."

Q:

What are the material U.S. federal income tax consequences of the merger to me?

A:

The exchange of shares of Tribune common stock by a shareholder for cash and shares of Sinclair Class A common stock in the merger will be a taxable transaction for U.S. federal income tax purposes. Accordingly, any shareholder that is a U.S. Holder (as defined in the section entitled "Material U.S. Federal Income Tax Consequences of the Merger") generally will recognize gain or loss for U.S. federal income tax purposes in an amount equal to the difference, if any, between (1) the sum of the amount of cash and the fair market value as of the effective time of the shares of Sinclair Class A common stock received in the merger and (2) the U.S. Holder's adjusted tax basis in the shares of Tribune common stock exchanged in the merger.

A shareholder that is a Non-U.S. Holder (as defined in the section entitled "Material U.S. Federal Income Tax Consequences of the Merger—Non-U.S. Holders") generally will not be subject to U.S. federal income tax with respect to the exchange of shares of Tribune common stock for cash and shares of Sinclair Class A common stock in the merger unless such Non-U.S. Holder has certain connections to the United States as described in "Material U.S. Federal Income Tax Consequences of the Merger—Non-U.S. Holders."

Please carefully review the information set forth in the section "Material U.S. Federal Income Tax Consequences of the Merger" on page 123 for a description of the material U.S. federal income tax consequences of the merger. The tax consequences of the merger will depend on your own situation. Please consult your own tax advisors as to the specific tax consequences of the merger to you.

Q:

When and where will the special meeting be held?

A:

The special meeting will be held at the Omni Hotel, located at 251 South Olive Street, Los Angeles, California 90012, on October 19, 2017 at 9:00 a.m., local time.

Q:

What are the proposals on which I am being asked to vote and what is the recommendation of the board with respect to each proposal?

A:

At the special meeting, you will be asked to:

•

consider and vote on a proposal to approve and adopt the merger agreement and the merger, which we refer to as the "merger proposal"; a copy of the merger agreement is attached as Annex A to this proxy statement/prospectus;

•

consider and vote on a non-binding, advisory proposal to approve the compensation that may become payable to Tribune's named executive officers in connection with the consummation of the merger, which we refer to as the "compensation proposal." See "Transaction Summary—

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Interests of Tribune's Directors and Executive Officers in the Merger" beginning on page 109 of this proxy statement/prospectus; and

•

consider and vote on a proposal to adjourn the special meeting, if necessary or appropriate, to solicit additional proxies if there are not sufficient votes to approve the merger proposal, which we refer to as the "adjournment proposal."

        Tribune does not expect any other business to be conducted at the special meeting.

Q:

What constitutes a quorum for the special meeting?

A:

Holders of record of a majority of the outstanding shares of Tribune Class A common stock and Tribune Class B common stock, counted as a single class, represented in person or by proxy, will constitute a quorum for the merger proposal at the special meeting. Holders of record of a majority of the outstanding shares of Tribune Class A common stock, represented in person or by proxy, will constitute a quorum for the compensation proposal and the adjournment proposal. Shares of Tribune Class A common stock and Tribune Class B common stock represented at the special meeting but not voted, including shares of Tribune Class A common stock and Tribune Class B common stock for which a shareholder directs an "abstention" from voting, will be counted as present for purposes of establishing a quorum. Broker non-votes (shares of Tribune Class A common stock and Tribune Class B common stock held by banks, brokerage firms or nominees that are present in person or by proxy at the special meeting but with respect to which the broker or other shareholder of record is not instructed by the beneficial owner of such shares how to vote on a particular proposal and the broker does not have discretionary voting power on such proposal), if any, will not be counted as present for purposes of establishing a quorum.

Q:

What vote is required to approve the proposals being presented at the special meeting?

A:

To be approved at the special meeting, the merger proposal will require the affirmative vote of the majority of the outstanding shares of Tribune common stock, voting as a single class, present, in person or represented by proxy and entitled to vote on the merger proposal. Abstentions and broker non-votes will have the effect of a vote against the merger proposal.

To be approved at the special meeting, the compensation proposal and the adjournment proposal (if necessary or appropriate) will each require the affirmative vote of the holders of a majority of the outstanding shares of Tribune Class A common stock present, in person or represented by proxy, at the special meeting and entitled to vote on the compensation proposal. Abstentions will have the effect of a vote against the compensation proposal and the adjournment proposal and broker non-votes will have no effect on the outcome of the vote on either proposal.

Q:

How does the Tribune board recommend that I vote at the special meeting?

A:

The Tribune board unanimously recommends that you vote "FOR" the merger proposal, "FOR" the compensation proposal and "FOR" the adjournment proposal, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement. See "Transaction Summary—Tribune's Reasons for the Transaction and Recommendation of the Tribune Board" beginning on page 66.

Q:

What is the effect if the merger proposal is not approved at the special meeting?

A:

If the merger proposal is not approved by the requisite vote at the special meeting or any adjournment thereof, then the transaction will not occur. Instead, Tribune would remain an independent public company, and the merger consideration would not be paid. Each of Sinclair and Tribune have the right to terminate the merger agreement under certain circumstances, including in the event of a failure to obtain the required shareholder vote. Upon a termination for

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failure to obtain the approval of the merger proposal at the special meeting, Tribune would be required to pay to Sinclair a termination fee equal to the sum of $38,500,000 plus Sinclair's costs and expenses, not to exceed $10,000,000. See "The Agreements—Description of the Merger Agreement—Termination" beginning on page 149.

Q:

Do I have appraisal or dissenters rights in connection with the transaction?

A:

Yes. Tribune shareholders are entitled to appraisal rights under Section 262 of the Delaware General Corporate Law, which we refer to as the "DGCL." See "Appraisal Rights." In addition, a copy of Section 262 of the DGCL is attached as Annex E to this proxy statement/prospectus.

Q:

Why am I being asked to consider and vote on a proposal to approve, by non-binding advisory vote, the transaction-related executive compensation?

A:

Under the rules of the U.S. Securities and Exchange Commission, which we refer to as the "SEC," Tribune is required to seek a non-binding, advisory vote with respect to the compensation that may be paid or become payable to its named executive officers in connection with the transaction.

Q:

What will happen if the compensation proposal is not approved at the special meeting?

A:

Approval of the transaction-related executive compensation is not a condition to closing of the transaction. Accordingly, you may vote against the compensation proposal and vote in favor of the merger proposal. The compensation proposal vote is an advisory vote and will not be binding on Tribune or Sinclair. If the transaction is completed, the compensation described in the compensation proposal will be paid to Tribune's named executive officers to the extent payable in accordance with the terms of their respective compensation agreements and contractual arrangements even if Tribune shareholders do not approve the compensation proposal.

Q:

Who is entitled to vote at the special meeting?

A:

The Tribune board has fixed the close of business on September 5, 2017 as the record date for the special meeting, which we refer to as the "record date." You are entitled to receive notice of, and vote at, the special meeting if you owned shares of Tribune common stock as of the record date.

Q:

How many votes do I have?

A:

You will be entitled to one vote for each share of Tribune Class A common stock that you owned on the record date on each of the proposals that will be voted upon at the special meeting. You will be entitled to one vote per share of Tribune Class B common stock that you owned as of the record date on the merger proposal and you are not entitled to vote shares of Tribune Class B common stock on either the compensation proposal or the adjournment proposal.

As of the record date, there were 87,282,099 shares of Tribune Class A common stock outstanding and 5,605 shares of Tribune Class B common stock outstanding. As of that date, less than 1% of the outstanding shares of Tribune Class A common stock were held by Tribune's directors and executive officers and no outstanding shares of Tribune Class B common stock were held by Tribune's directors and executive officers, not including approximately 16.3% of the outstanding shares as of the close of business on May 4, 2017 of Tribune Class A common stock beneficially owned by the Oaktree shareholders (as described below), which the Oaktree shareholders have agreed to vote in favor of the approval of the merger proposal and the other transactions contemplated by the merger agreement.

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Q:

Are any shareholders already committed to vote in favor of the merger proposal?

A:

Yes. Affiliates of Oaktree Capital Management, which we refer to as the "Oaktree shareholders," have entered into a voting and support agreement with Sinclair, which we refer to as the "voting agreement," in which they have agreed, among other things, to vote their shares of Tribune Class A common stock in favor of the approval of the merger proposal and the other transactions contemplated by the merger agreement. These shares represent approximately 16.3% of the issued and outstanding shares of Tribune common stock as of the close of business on May 4, 2017.

The voting agreement is attached to this proxy statement/prospectus as Annex B and is incorporated by reference into this proxy statement/prospectus.

Q:

What if my broker, bank or other nominee holds my shares in "street name"?

A:

If a broker, bank or other nominee holds your shares for your benefit but not in your own name, such shares are in "street name." In that case, your broker, bank or other nominee will send you a voting instruction form to use in order to instruct the vote of your shares. The availability of telephone and Internet voting depends on the voting procedures of your broker, bank or other nominee. Brokers, banks or other nominees will not have discretionary authority on any matter at the special meeting, and thus will not vote on any matter at the special meeting without having received a properly completed voting instruction form. With respect to the merger proposal, a broker non-vote will have the effect of a vote against the proposal. With respect to the compensation proposal and the adjournment proposal, a broker non-vote will have no effect on such proposals.

In accordance with the rules of the New York Stock Exchange, which we refer to as the "NYSE," banks, brokerage firms and other nominees who hold shares of Tribune common stock in "street name" for their customers have authority to vote on "routine" proposals when they have not received instructions from beneficial owners. However, banks, brokerage firms and other nominees are precluded from exercising their voting discretion with respect to non-routine matters, such as the adoption of the merger agreement, the proposal to approve, by non-binding advisory vote, the transaction-related executive compensation and adjournments of the special meeting, if necessary or appropriate, to solicit additional proxies if there are insufficient votes at the time of the special meeting to adopt the merger agreement. As a result, absent specific instructions from the beneficial owner of such shares, banks, brokerage firms and other nominees are not empowered to vote such shares.

Q:

How do I vote?

A:

After reading and carefully considering the information contained in this proxy statement/prospectus, please submit a proxy or voting instructions for your shares of Tribune common stock as promptly as possible so that your shares will be represented at the special meeting. You may submit your proxy or voting instructions before the special meeting in one of the following ways:

By Internet.    Use the Internet at www.proxyvote.com to submit your proxy or voting instructions and for the electronic delivery of information up until 11:59 p.m. Eastern Time on October 18, 2017. Have your proxy card or voting instructions in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. The availability of Internet voting for beneficial owners holding shares of Tribune common stock in "street name" will depend on the voting process of your broker, bank or other nominee. If you are a beneficial owner of shares of Tribune's common stock held in "street name," please follow the voting instructions in the materials you receive from your broker, bank or other nominee.

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By Phone.    Use any touch-tone telephone to dial 1-800-690-6903 to submit your proxy or voting instructions up until 11:59 p.m. Eastern Time on October 18, 2017. Have your proxy card or voting instructions in hand when you call and then follow the instructions. If you submit a proxy or voting instructions by telephone, do not return your proxy card or voting instructions. The availability of telephone voting for beneficial owners holding shares of Tribune common stock in "street name" will depend on the voting process of your broker, bank or other nominee. If you are a beneficial owner of shares of Tribune common stock held in "street name," please follow the voting instructions in the materials you receive from your broker, bank or other nominee.

By Mail.    Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. Broadridge must receive your proxy card no later than the close of business on October 18, 2017. If you are a beneficial owner of shares of Tribune common stock held in "street name," please follow the voting instructions in the materials you receive from your broker, bank or other nominee.

In addition, all shareholders may vote in person at the special meeting. In order to attend the special meeting, you must (i) be a holder of shares of Tribune common stock as of the record date, (ii) present valid photo identification issued by a government agency, such as a driver's license or passport and (iii) if you are a beneficial owner of shares of Tribune common stock held in "street name," present a brokerage statement showing that you owned shares of Tribune common stock as of the record date. Note that if your shares are held in the name of your broker, bank or other nominee and you wish to attend or vote in person at the special meeting, you must contact your broker, bank or other nominee and request a document called a "legal proxy." You must bring this legal proxy to the meeting in order to vote in person. For additional information on voting procedures, see "Special Meeting and Proposals" beginning on page 48.

After reading and carefully considering the information contained in this proxy statement/prospectus, please submit your proxy or voting instructions as soon as possible even if you plan to attend the special meeting.

Q:

What do I do if I receive more than one set of voting materials?

A:

You may receive more than one set of voting materials, including multiple copies of this proxy statement/prospectus and multiple proxy cards or voting instruction cards. For example, if you hold your shares in more than one brokerage account, you will receive a separate instruction card for each brokerage account in which you hold shares. If you are a holder of record and your shares are held in more than one name, you will receive more than one proxy card. Please complete, sign, date and return each proxy card and voting instructions you receive, or submit each proxy or voting instruction by telephone or Internet by following the instructions on your proxy cards or the voting instruction.

Q:

How will my proxy be voted?

A:

If you submit a proxy or voting instructions by completing, signing, dating and mailing your proxy card, or over the Internet or by telephone, your shares will be voted in accordance with your instructions. If you are a shareholder of record as of the record date and you sign, date, and return your proxy card but do not indicate how you want to vote on any particular proposal and do not indicate that you wish to abstain with respect to that particular proposal, the shares of Tribune common stock represented by your proxy will be voted in favor of any proposal on which the Tribune shareholder is entitled to vote. However, if you are a holder of Tribune Class A common stock and you sign, date and return your proxy card and indicate that you vote against the merger proposal, but do not indicate how you want to vote on the compensation proposal or the adjournment proposal, the shares of Tribune Class A common stock represented by your proxy

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will not be voted in favor of the compensation proposal or the adjournment proposal. If you are a beneficial owner, your broker, bank or other nominee will vote your shares on each of the merger proposal, the compensation proposal and the adjournment proposal only if you provide instructions on how to vote by filling out the voting instruction form sent to you by your broker, bank or other nominee with this proxy statement/prospectus.

Q:

Can I revoke or change my vote after I have submitted a proxy or voting instruction card?

A:

Yes. You can change your vote in one of three ways:

•

you can send a signed notice of revocation, which must be received prior to the beginning of the special meeting, to Tribune's Corporate Secretary, as appropriate;

•

you can submit a revised proxy bearing a later date by mail, over the Internet or by telephone as described above, which revised proxy must be received prior to the deadlines set forth above for each method of voting; or

•

you can attend the special meeting and vote in person, which will automatically cancel any proxy previously given, though your attendance alone will not revoke any proxy that you have previously given.

If you are a beneficial owner of shares of Tribune common stock held in "street name," you must contact your broker, bank or other nominee to change your vote or obtain a written legal proxy to vote your shares if you wish to cast your vote in person at the applicable meeting.

Q:

How will I receive the merger consideration to which I am entitled?

A:

If you hold physical stock certificates of Tribune common stock, you will be sent a letter of transmittal shortly after the effective time, describing how you may exchange your shares of Tribune common stock for the merger consideration, and the exchange agent will forward to you the cash and the Sinclair Class A common stock in book-entry form (or applicable evidence of ownership) to which you are entitled, including cash in lieu of fractional shares and dividends on Sinclair Class A common stock, if any, with a record date and payment date after the effective time, after receiving the proper documentation from you. If you hold your shares of Tribune common stock in book-entry form, you are not required to take any specific actions to exchange your shares of Tribune common stock, and after the completion of the transaction, such shares will be automatically exchanged for the merger consideration, cash in lieu of fractional shares and dividends on Sinclair Class A common stock, if any, with a record date and payment date after the effective time.

You should not send your stock certificate representing your Tribune common stock until the receipt from the exchange agent of the letter of transmittal. Please do not send in your stock certificates now. See "The Agreements—Description of the Merger Agreement—Exchange and Payment Procedures in the Merger" beginning on page 129.

Q:

What happens if I sell my shares after the record date but before the special meeting?

A:

If you transfer your shares of Tribune common stock after the record date but before the date of the special meeting, you will retain your right to vote at the special meeting, but you will not have the right to receive for those shares any merger consideration for the shares that you transferred. You must hold your shares through the closing of the transaction in order to receive merger consideration for those shares.

Q:

May I change my vote after I have delivered my proxy or voting instruction card?

A:

Yes. Any Tribune shareholder giving a proxy has the power to revoke it at any time before it is exercised. Tribune shareholders of record may revoke their proxy by filing an instrument of

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revocation or a duly executed proxy bearing a later date (including by means of a telephone or Internet vote) with Tribune's Corporate Secretary at 435 North Michigan Avenue, Chicago, Illinois 60611. As a Tribune shareholder of record, you may also revoke a proxy by attending the special meeting, and voting in person. Attendance at the special meeting alone will not revoke any proxy. If not revoked, the proxy will be voted at the special meeting, in accordance with your instructions.

If your shares are held in an account at a broker, bank or other nominee and you have delivered your voting instruction card to your broker, bank or other nominee, you should contact your broker, bank or other nominee to change your vote.

Q:

Where can I find more information about the parties to the transaction?

A:

You can find more information about Sinclair and Tribune by reading the sections of the proxy statement/prospectus titled "Transaction Summary—Parties to the Transaction" beginning on page 55 and "Where You Can Find More Information" beginning on page 187.

Q:

Who will count the votes?

A:

The votes will be counted by American Election Services, LLC, the appointed inspector for the special meeting.

Q:

Will a proxy solicitor be used?

A:

Tribune has engaged Innisfree to assist in the solicitation of proxies and provide related advice and informational support for a services fee of approximately $25,000, plus reasonable out-of-pocket fees and expenses for these services, as described under "Special Meeting and Proposals" beginning on page 48.

Q:

How do I obtain the voting results from the special meeting?

A:

Preliminary voting results will be announced at the special meeting and will be set forth in a press release that Tribune intends to issue after the special meeting. The press release will be available on Tribune's website. Final voting results for the special meeting is required to be filed in a Current Report on Form 8-K filed with the SEC within four business days after the meeting.

Q:

Whom should I contact if I have any questions about these materials or voting?

A:

If you have any questions about the proxy materials or if you need assistance submitting your proxy or voting instructions or voting your shares or need additional copies of this document or the enclosed proxy card, you should contact the proxy solicitation agent for the company in which you hold shares as set forth below:

Innisfree M&A Incorporated
501 Madison Avenue, 20th Floor
New York, New York 10022
(888) 750-5834

Shareholders Call Toll Free: (888) 750-5834
Banks and Brokerage Firms Call: (212) 750-5833

If your shares are held "street name," through a bank, broker or other nominee, you should contact such bank, broker or other nominee if you need to obtain voting instruction cards or have questions on how to vote your shares.

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No Solicitation (See Page 138)page 97)

As more fully described in this proxy statement/prospectusstatement and as set forth in the merger agreement, Tribune has agreed, among other things, not to:

•

solicit, initiate or knowingly encourage or knowingly facilitate any offer, proposal or indication of interest (whether or not in writing) from any person or “group” of persons (as defined in Section 13(d)

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