UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 20142015

or

For the transition period from                    to                    

Commission File Numbers of issuing entity in respect of the notes:

333-141703-02, 333-191359, 333-167413

Commission File Numbers of issuing entity in respect of the Series 2007-CC Collateral Certificate:

000-23108, 333-191359-02, 333-167413-02

Commission File Numbers of depositor and sponsor:

033-54804, 333-191359-01, 333-167413-01

DISCOVER CARD EXECUTION NOTE TRUST

(Exact name of issuing entity in respect of the notes as specified in its charter)

Commission File Numbers of issuing entity in respect of the notes:

333-141703-02, 333-167413, 333-191359, 333-205455-01

Central Index Key Number of issuing entity in respect of the notes: 0001407200

DISCOVER CARD MASTER TRUST I

(Exact name of issuing entity in respect of the Series 2007-CC Collateral Certificate as specified in its charter)

Commission File Numbers of issuing entity in respect of the Series 2007-CC Collateral Certificate:

000-23108, 333-141703, 333-167413-02, 333-191359-02, 333-205455-02

Central Index Key Number of issuing entity in respect of the Series 2007-CC Collateral Certificate:

0000894329

DISCOVER BANK

(Exact name of depositor and sponsor as specified in its charter)

Commission File Numbers of sponsor:

033-54804, 333-141703-01, 333-167413-01, 333-191359-01

Central Index Key Number of sponsor: 0000894327

DISCOVER FUNDING LLC

(Exact name of depositor as specified in its charter)

Commission File Number of depositor:

333-205455

Central Index Key Number of depositor: 0001645731

Depositor’s telephone number, including area code: (302) 323-7315

Securities registered pursuant to Section 12(b) of the Act:None None

Securities registered pursuant to Section 12(g) of the Act:None None

Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act.    Yes  ¨    No    x

Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act.    Yes  ¨    No    x

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    Yes  x    No    ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).    Yes  x    No  ¨

Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (§ 229.405) is not contained herein, and will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.    x

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, or a non-accelerated filer, or a smaller reporting company. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Act).     Yes  ¨    No  x

State the aggregate market value of the voting and non-voting common equity held by non-affiliates computed by reference to the price at which the common equity was last sold, or the average bid and asked price of such common equity, as of the last business day of the registrant’s most recently completed second fiscal quarter.

Registrant has no voting or non-voting common equity outstanding held by non-affiliates.

PART I

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 1. Business.

Item 1A. Risk Factors.

Item 2. Properties.

Item 3. Legal Proceedings.

Item 1B. Unresolved Staff Comments.

Not applicable.

Item 4. Mine Safety Disclosures.

Not applicable.

Substitute information provided in accordance with General Instruction J to Form 10-K:

Item 1112(b) of Regulation AB. Significant Obligors of Pool Assets (Financial Information).

The primary asset of Discover Card Execution Note Trust (the “Note Issuance Trust”) is the Discover Card Master Trust I, Series 2007-CC collateral certificate, which represents an undivided interest in Discover Card Master Trust I (the “Master Trust”), whose assets include Discover Card receivables existing as of specified dates in designated accounts, which receivables have been transferred to the Master Trust by Discover Bank.Bank and Discover Funding LLC, as applicable. The investor interest in receivables for the collateral certificate reflects the aggregate nominal liquidation amount of notes issued by the Note Issuance Trust. The Master Trust, therefore, may be considered a significant obligor in relation to the Note Issuance Trust. Pursuant to Instruction 3.b. to Item 1112(b) of Regulation AB, the information required by Instruction J to Form 10-K in respect of the Master Trust has been disclosed in this report on Form 10-K in lieu of the information otherwise contemplated by Item 1112(b).

The pool assets held by the Master Trust do not include any significant obligors.

Item 1114(b)(2) of Regulation AB. Credit Enhancement and Other Support, Except for Certain Derivatives Instruments (Information Regarding Significant Enhancement Providers) (Financial Information).

Not applicable.

Item 1115(b) of Regulation AB. Certain Derivatives Instruments (Financial Information).

Not applicable.

Item 1117 of Regulation AB. Legal Proceedings.

Discover Bank

In the normal course of business, from time to time, Discover Bank and/or one or more of its affiliates have been named as a defendant in various legal actions, including arbitrations, class actions, and other litigation, arising in connection with our activities. Certain of the actual or threatened legal actions include claims for substantial compensatory and/or punitive damages or claims for indeterminate amounts of damages. Discover Bank contests liability and/or the amount of damages as appropriate in each pending matter.

Discover Bank has historically relied on the arbitration clause in its cardmember agreements, which has in some instances limited the costs of, and our exposure to, litigation, but there can be no assurance that Discover Bank will continue to be successful in enforcing theits arbitration clause in the future. Legal challenges to the enforceability of these clauses have led most card issuers and may cause Discover Bank to discontinue their use. In addition, billsDiscover Bank

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and/or one or more of its affiliates is involved in pending legal actions challenging its arbitration clause. Bills are periodically introduced in Congress to directly or indirectly prohibit the use of pre-dispute arbitration clauses, and the Dodd-Frank Act authorized the CFPB to conduct a study on pre-dispute arbitration clauses and, based on the study, potentially limit or ban arbitration clauses. On March 10, 2015, the CFPB released its report to Congress on pre-dispute arbitration clauses. A preliminary reportas required by the Dodd-Frank Act. On October 7, 2015, the CFPB announced that it was considering proposing rules on arbitration agreements issued bythat would (i) effectively ban consumer financial companies from using arbitration clauses to prevent class action cases and (ii) require records of all other arbitrations to be provided to the CFPB expressed concerns about these clauses that may signal the agency is contemplating action to limit or ban such clauses. Further, Discover Bank and/or one or morefor potential publication on its website. The timing and provisions of its affiliatesany final rule are involved in pending legal actions challenging the arbitration clause.uncertain at this time.

Discover Bank and its affiliates are also involved, from time to time, in other reviews, investigations and proceedings (both formal and informal) by governmental regulatory and enforcement agencies regarding our business, including, among other matters, accounting, tax and operational matters, some of which may result in adverse judgments, settlements, fines, penalties, injunctions, decreases in regulatory ratings or other relief, which could materially impact Discover Bank’s financial results, increase its cost of operations, require a change in business activities and product offerings or limit its ability to execute its business strategies and engage in certain business activities. As described below, the CFPB recently concluded an investigation into certain student loan practices of Discover Bank. Litigation and regulatory actions could also adversely affect Discover Bank’s reputation.

On June 13, 2014, Discover Bank entered into a Consent Order with the FDIC to resolve previously disclosed matters related to the FDIC’s examination of Discover Bank’s anti-money laundering and related compliance programs. In the Consent Order, Discover Bank agreed to, among other things, enhance its anti-money laundering and related compliance programs. The order does not include civil money penalties.penalties but does cause Discover Bank to incur significant expenses. The Federal Reserve recently notified Discover Financial Services in 2014 of its intention to enter into a supervisory action to require enhancements to the Company’s enterprise-wide anti-money laundering and related compliance programs.

On July 22, 2015, Discover Bank, The Student Loan Corporation and Discover Products Inc. (“DPI”) agreed to a consent order with the CFPB is currently investigatingresolving the CFPB’s investigation into certain student loan servicing practicespractices. The consent order requires Discover Bank, The Student Loan Corporation and DPI to provide redress of approximately $16 million to consumers who may have been affected by the activities described in the consent order related to certain collection calls, overstatements of minimum payment due amounts in billing statements and provision of interest paid information to consumers, and provide regulatory disclosures with respect to loans acquired in default. In addition, Discover Bank. IfBank, The Student Loan Corporation and DPI are required to pay a $2.5 million civil money penalty to the CFPB. As required by the consent order, on October 19, 2015, Discover Bank, the Student Loan Corporation and DPI submitted to the CFPB determinesa redress plan and a compliance plan designed to bring an enforcement action, it could include demands for civil money penalties, changes to certainensure that they provide redress and otherwise comply with the terms of Discover Bank’s business practices and customer restitution. Given that the CFPB is a relatively new agency and is continuing to develop its approaches to fulfilling its statutory mandate, we cannot at this time predict the extent to which CFPB actions may affect Discover Bank or the consumer finance markets in which it operates.order.

U.S. Bank National Association

In JuneSince 2014 a civil complaint wasvarious plaintiffs or groups of plaintiffs, primarily investors, have filed in the Supreme Court of the State of New York, New York County, by a group of institutional investorsclaims against U.S. Bank National Association (“U.S. Bank”Bank”), in its capacity as trustee or successor trustee (as the case may be) under certain residential mortgage backed securities (“RMBS”RMBS”) trusts. The plaintiffs are investment funds formed by nine investment advisors (AEGON, BlackRock, Brookfield, DZ Bank, Kore, PIMCO, Prudential, Sealink and TIAA) that purport to be bringing suit derivatively on behalf of 841 RMBS trusts that issued $771 billion in original principal amount of securities between 2004 and 2008. According to the plaintiffs, cumulative losses for these RMBS trusts equal $92.4 billion as of the date of the complaint. The complaint is one of sixor plaintiff groups have filed substantially similar complaints filed against other RMBS trustees, (Deutscheincluding Deutsche Bank, Citibank, HSBC, Bank of New York Mellon and Wells Fargo) by certain of these plaintiffs.Fargo. The complaintcomplaints against U.S. Bank allegesallege the trustee caused losses to investors as a result of alleged failures by the sponsors, mortgage loan sellers and servicers for these RMBS trusts and assertsassert causes of action based upon the trustee’s purported failure to enforce repurchase obligations of mortgage loan sellers for alleged breaches of representations and warranties concerning loan quality. The complaintcomplaints also assertsassert that the trustee failed to notify securityholders of purported events of default allegedly caused by breaches of servicing standards by mortgage loan servicers and that the trustee purportedly failed to abide by appropriate standardsa heightened standard of care following alleged events of default. Relief sought includes money damages

Currently U.S. Bank is a defendant in an unspecified amountmultiple actions alleging individual or class action claims against the trustee with respect to multiple trusts as described above with the most substantial case being:BlackRock Balanced Capital Portfolio et al v. U.S. Bank National Association, No. 605204/2015 (N.Y. Sup. Ct.) (class action alleging

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claims with respect to approximately 794 trusts) and equitable relief. In November 2014,its companion caseBlackRock Core Bond Portfolio et al v. U.S. Bank National Association, No. 14-cv-9401 (S.D.N.Y.). Some of the plaintiffs sought leave to voluntarily dismiss their original state court complaint and filed a substantially similar complainttrusts implicated in the United States District Court for the Southern Districtaforementioned Blackrock cases, as well as other trusts, are involved in actions brought by separate groups of New York. The federal civil complaint added a class action allegation and a change in the total number of namedplaintiffs related to no more than 100 trusts to 843 RMBS trusts. In December 2014, the plaintiffs’ motion to voluntarily dismiss their original state court complaint was granted. Other cases alleging similar causes of action have previously been filed against per case.

U.S. Bank and other trustees by RMBS investors in other transactions.

There can be nodoes not provide any assurances as to the outcome of any of the litigation, or the possible impact of the litigationthese litigations on the trusteeU.S. Bank or the RMBS trusts. However, U.S. Bank denies liability and believes that it has performed its obligations under the RMBS trusts in good faith, that its actions were not the cause of losses to investors and that it has meritorious defenses, and it intends to contest the plaintiffs’ claims vigorously.

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Other than as set forth above, there are no legal proceedings pending or known to be contemplated by authorities against any of U.S. Bank National Association, as indenture trustee, Wilmington Trust Company, as owner trustee, Discover Bank, as sponsor depositor, and servicer, Discover Card Master Trust I, as issuing entity of the collateral certificate, Discover Card Execution Note Trust, as issuing entity of the notes, Discover Funding LLC, as depositor, or any sub-servicer, or of which any property of the foregoing is subject, that are material to holders of the notes.

PART II

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 5. Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities.

Item 6. Selected Financial Data.

Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

Item 8. Financial Statements and Supplementary Data.

Item 9. Changes in and Disagreements with Accountants on Accounting and Financial Disclosure.

Item 9A. Controls and Procedures.

Item 9B. Other Information.

None.

PART III

The following Items have been omitted in accordance with General Instruction J to Form 10-K:

Item 10. Directors, Executive Officers and Corporate Governance.

Item 11. Executive Compensation.

Item 12. Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.

Item 13. Certain Relationships and Related Transactions, and Director Independence.

Item 14. Principal Accountant Fees and Services.

Substitute information provided in accordance with General Instruction J to Form 10-K:

Item 1119 of Regulation AB. Affiliations and Certain Relationships and Related Transactions.

Discover Bank, which, actsprior to January 1, 2016, acted as seller/depositor for the Master Trust, depositor and beneficiary for the Note Issuance Trust and, at all times, acts as the sponsor of their securitizations, is a wholly owned subsidiary of Discover Financial Services. Discover Funding LLC was established on May 18, 2015 as a wholly-owned subsidiary of Discover Bank and, on and after January 1, 2016, acts as depositor and beneficiary for the Note Issuance Trust and as holder of the residual transferor interest of the Master Trust. Discover Financial Services acquired Discover Bank in January 1985. Discover Bank and the trustee for the Master Trust formed the Master Trust in October 1993. Discover Bank originates and prior to January 1, 2016, has transferred to the Master Trust, since its formation, the credit card receivables generated under certain designated Discover card accounts. On

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and after January 1, 2016, Discover Bank transfers such credit card receivables to Discover Funding LLC for further transfer to the Master Trust. Discover Bank and the owner trustee formed the Note Issuance Trust on July 2, 2007. Discover Bank transferred an undivided interest in the receivables and other assets of the Master Trust, represented by the collateral certificate, to the Note Issuance Trust to support the issuance of notes on July 26, 2007.

Discover Bank acts as master servicer for the Master Trust and is currently the only servicer under the Pooling and Servicing Agreement with respect to the receivables. During the reporting period, Discover Bank outsourced certain servicing functions to the following affiliates: DB Servicing Corporation (“DBSC”) and Discover Products Inc. (“its affiliate, DPI. DPI”). DBSC contracted with BancTec, Inc., a third-party service provider, for certain check processing and related services. However, Discover Bank is ultimately responsible for the overall servicing function. DBSC was and DPI is held directly by Discover Bank. Effective as of 11:59 p.m. EST on December 31, 2014, DBSC merged into DPI, with DPI being the only surviving entity. Discover Bank also acts as calculation agent for the Note Issuance Trust, which is part of the servicing function.

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Item 1122 of Regulation AB. Compliance with Applicable Servicing Criteria.

Each of Discover Bank, DPI, DBSC, BancTec, Inc. and U.S. Bank National Association (each, a “Servicing Participant”) has been identified by the registrant as a party participating in the servicing function during the reporting period with respect to the pool assets held by each of the Master Trust and the Note Issuance Trust. Each of Discover Bank, DPI, (for itself and as successor in interest to DBSC), BancTec, Inc. and U.S. Bank National Association has completed a report on an assessment of compliance with the servicing criteria applicable to such Servicing Participant (each, a “Report on Assessment”) during the year ended December 31, 2014,2015, which Reports on Assessment are attached as exhibits to this Form 10-K. In addition, each of Discover Bank, DPI, (for itself and as successor in interest to DBSC), BancTec, Inc. and U.S. Bank National Association has provided an attestation report (each, an “Attestation Report”) by a registered independent public accounting firm regarding its related Report on Assessment. Each Attestation Report is attached as an exhibit to this Form 10-K. None of the Reports on Assessment or the related Attestation Reports has identified any material instances of noncompliance with the servicing criteria applicable to such Servicing Participant described in the related Report on Assessment.

Item 1123 of Regulation AB. Servicer Compliance Statement.

Each of Discover Bank DPI, and DBSCDPI has been identified by the registrant as a servicer during the reporting period with respect to the pool assets held by each of the Master Trust and the Note Issuance Trust. Each of Discover Bank and DPI (for itself and as successor in interest to DBSC) has provided a statement of compliance (each, a “Compliance Statement”) with respect to the servicing activities conducted during the Note Issuance Trust’s year ended December 31, 2014,2015, signed by an authorized officer, and each such Compliance Statement is attached as an exhibit to this Form 10-K.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

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SIGNATURES

Pursuant to the requirements of Section 13 of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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EXHIBIT INDEX

7

7

8

8

9

10

9

10

11

12