UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-K

(Mark One)

For the fiscal year ended December 31, 2020

or

For the transition period from                      to                     

333-189017-09

(Commission File Number of issuing entity)

0001643661

(Central Index Key Number of issuing entity)

Citigroup Commercial Mortgage Trust 2015-GC31

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

333-189017

(Commission File Number of depositor)

0001258361

(Central Index Key Number of depositor)

Citigroup Commercial Mortgage Securities Inc.

(Exact name of depositor as specified in its charter)

Citigroup Global Markets Realty Corp.

(Central Index Key Number: 0001541001)

Goldman Sachs Mortgage Company

(Central Index Key Number: 0001541502)

LMF Commercial, LLC (f/k/a Rialto Mortgage Finance, LLC)

(Central Index Key Number: 0001592182)

RAIT Funding, LLC

(Central Index Key Number: 0001587045)

KGS-Alpha Real Estate Capital Markets, LLC

(Central Index Key Number: 0001499542)

(Exact name of sponsor as specified in its charter)

c/o Citibank, N.A.

388 Greenwich Street, 14^th Floor

New York, New York 10013

(Address of principal executive offices of issuing entity)

(212) 816-5614

Registrant’s telephone number, including area code

Securities registered pursuant to Section 12(b) of the Act:

Securities registered pursuant to Section 12(g) of the Act:  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

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

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    ☐  No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted 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 such files).

Not Applicable

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act.  ☐

Indicate by check mark whether the registrant has filed a report on and attestation to its management’s assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.     ☐

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

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.

Not Applicable

Indicate by check mark whether the registrant has filed all documents and reports required to be filed by Section 12, 13 or 15(d) of the Securities Exchange Act of 1934 subsequent to the distribution of securities under a plan confirmed by a court.

Not Applicable

Indicate the number of shares outstanding of each of the registrant’s classes of common stock, as of the latest practicable date.

Not Applicable

DOCUMENTS INCORPORATED BY REFERENCE

List hereunder the following documents if incorporated by reference and the Part of the Form 10-K (e.g., Part I, Part II, etc.) into which the document is incorporated: (1) Any annual report to security holders; (2) Any proxy or information statement; and (3) Any prospectus filed pursuant to Rule 424(b) or (c) under the Securities Act of 1933. The listed documents should be clearly described for identification purposes (e.g., annual report to security holders for fiscal year ended December 24, 1980).

Not Applicable

PART I

Item 1. Business.

Omitted.

Item 1A. Risk Factors.

Omitted.

Item 1B. Unresolved Staff Comments.

None.

Item 2. Properties.

Omitted.

Item 3. Legal Proceedings.

Omitted.

Item 4. Mine Safety Disclosures.

Not applicable.

PART II

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

Omitted.

Item 6. Selected Financial Data.

Omitted.

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

Omitted.

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

Omitted.

Item 8. Financial Statements and Supplementary Data.

Omitted.

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

Omitted.

Item 9A. Controls and Procedures.

Omitted.

Item 9B. Other Information.

None.

PART III

Item 10. Directors, Executive Officers and Corporate Governance.

Omitted.

Item 11. Executive Compensation.

Omitted.

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

Omitted.

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

Omitted.

Item 14. Principal Accountant Fees and Services.

Omitted.

ADDITIONAL DISCLOSURE ITEMS REQUIRED BY GENERAL INSTRUCTION J(2)

Item 1112(b) of Regulation AB

The property securing the 135 South LaSalle mortgage loan constitutes a significant obligor within the meaning of Item 1101(k)(2) of Regulation AB and as disclosed in the prospectus supplement for Citigroup Commercial Mortgage Trust 2015-GC31 filed on July 8, 2015. With respect to the property securing the 135 South LaSalle mortgage loan, the most recent unaudited net operating income was $18,096,440 from January 1, 2020 through December 31, 2020.

Item 1114(b)(2) and Item 1115(b) of Regulation AB

No entity or group of affiliated entities provides any external credit enhancement, uses any derivative instruments or other support for the certificates within this transaction.

Item 1117 of Regulation AB

Disclosure from Deutsche Bank Trust Company Americas, as Trustee:

Deutsche Bank Trust Company Americas (“DBTCA”) and Deutsche Bank National Trust Company (“DBNTC”) have been sued by investors in civil litigation concerning their role as trustees of certain residential mortgage-backed securities (“RMBS”) trusts.

On June 18, 2014, a group of investors, including funds managed by Blackrock Advisors, LLC, PIMCO-Advisors, L.P., and others, filed an action against DBNTC and DBTCA in New York State Supreme Court alleging that DBNTC and DBTCA failed to perform purported duties, as trustees for 544 private-label RMBS trusts, to enforce breaches of representations and warranties as to mortgage

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loans held by the trusts and to enforce breaches by servicers of their mortgage loan servicing obligations for the trusts.  During the course of the litigation, plaintiffs dismissed the case from New York State Supreme Court and refiled two separate cases, one in the U.S. District Court for the Southern District of New York (the “BlackRock SDNY Case”) and the other in the Superior Court of California, Orange County (the “BlackRock California Case”).  Pursuant to a settlement among the parties, the BlackRock SDNY Case was dismissed on December 6, 2018 and the BlackRock California Case was dismissed on January 11, 2019.

On September 27, 2017, DBTCA was added as a defendant to a case brought by certain special purpose entities including Phoenix Light SF Limited in the U.S. District Court for the Southern District of New York, in which the plaintiffs previously alleged incorrectly that DBNTC served as trustee for all 43 of the trusts at issue.  On September 27, 2017, plaintiffs filed a third amended complaint that names DBTCA as a defendant in addition to DBNTC.  DBTCA serves as trustee for one of the 43 trusts at issue.  DBNTC serves as trustee for the other 42 trusts at issue.  Plaintiffs’ third amended complaint brings claims for violation of the U.S. Trust Indenture Act of 1939 (“TIA”); breach of contract; breach of fiduciary duty; negligence and gross negligence; violation of New York’s Streit Act; and breach of the covenant of good faith.  However, in the third amended complaint, plaintiffs acknowledge that, before DBTCA was added to the case, the court dismissed plaintiffs’ TIA Act claims, negligence and gross negligence claims, Streit Act claims, claims for breach of the covenant of good faith, and certain theories of plaintiffs’ breach of contract claims, and plaintiffs only include these claims to preserve any rights on appeal.  Plaintiffs allege damages of “hundreds of millions of dollars.”  On November 13, 2017, DBNTC and DBTCA filed an answer to the third amended complaint.  On December 7, 2018, DBNTC and DBTCA filed a motion for summary judgment.  Also on December 7, 2018, plaintiffs, jointly with Commerzbank AG (see description of Commerzbank case below), filed a motion for partial summary judgment.  As of March 1, 2021, both motions for summary judgment have been briefed and are awaiting decision by the court.

On November 30, 2017, DBTCA was added as a defendant to a case brought by Commerzbank AG (“Commerzbank”) in the U.S. District Court for the Southern District of New York, in which Commerzbank previously alleged incorrectly that DBNTC served as trustee for all 50 of the trusts at issue.  On November 30, 2017, Commerzbank filed a second amended complaint that names DBTCA as a defendant in addition to DBNTC.  DBTCA serves as trustee for 1 of the 50 trusts at issue.  DBNTC serves as trustee for the other 49 trusts at issue.  Commerzbank’s second amended complaint brings claims for violation of the TIA; breach of contract; breach of fiduciary duty; negligence; violation of the Streit Act; and breach of the covenant of good faith.  However, in the second amended complaint, Commerzbank acknowledges that, before DBTCA was added to the case, the court dismissed Commerzbank’s TIA claims for the trusts governed by pooling and servicing agreements, as well as its Streit Act claims and claims for breach of the covenant of good faith, and Commerzbank only includes these claims to preserve any rights on appeal.  The second amended complaint alleges that DBNTC and DBTCA caused Commerzbank to suffer “hundreds of millions of dollars in losses,” but the complaint does not include a demand for money damages in a sum certain.  On January 29, 2018, DBNTC and DBTCA filed an answer to the second amended complaint.  On December 7, 2018, DBNTC and DBTCA filed a motion for summary judgment.  Also on December 7, 2018, Commerzbank, jointly with the Phoenix Light plaintiffs, filed a motion for partial summary judgment.  As of March 1, 2021, both motions for summary judgment have been briefed and are awaiting decision by the court.

On December 30, 2015, IKB International, S.A. in Liquidation and IKB Deutsche Industriebank A.G. (collectively, “IKB”), as an investor in 37 RMBS trusts, filed a summons with notice in the Supreme Court of the State of New York, New York County, against DBNTC and DBTCA as trustees of the trusts.  On May 27, 2016, IKB served its complaint asserting claims for breach of contract, breach of fiduciary duty, breach of duty to avoid conflicts of interest, violation of the Streit Act, violation of the TIA, violation of Regulation AB, and violation of Section 9 of the Uniform Commercial Code.  IKB alleges that DBNTC and DBTCA are liable for over U.S. $268 million in damages.  On October 5, 2016, DBNTC and DBTCA, together with several other trustees defending lawsuits by IKB, filed a joint motion to dismiss.  On January 6, 2017 and June 20, 2017, IKB voluntarily dismissed with prejudice all claims as to seven trusts.  On January 27, 2021, the court granted in part and denied in part DBNTC and DBTCA’s motion to dismiss.  The court granted the motion to dismiss with respect to IKB’s claims for violations of the Streit Act, Regulation AB, and Section 9 of the Uniform Commercial Code, as well as certain aspects of IKB’s claims for breach of contract, breach of fiduciary duty, and violation of the TIA.  The court denied the remainder of the motion to dismiss.  IKB’s remaining claims for breach of contract, breach of fiduciary duty, breach of duty to avoid conflicts of interest, and violation of the TIA will proceed.

It is DBTCA’s belief that it has no pending legal proceedings (including, based on DBTCA’s present evaluation, the litigation disclosed in the foregoing paragraphs) that would materially affect its ability to perform its duties under the related servicing agreement for this transaction.

Item 1119 of Regulation AB

Provided previously in the prospectus supplement of the Registrant relating to the issuing entity and filed on July 8, 2015 pursuant to Rule 424(b)(5) of the Securities Act of 1933, as amended.

Item 1122 of Regulation AB

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The reports on assessment of compliance with servicing criteria for asset-backed securities and related attestation reports are attached hereto under Item 15.

Item 1123 of Regulation AB

The servicer compliance statements are attached hereto under Item 15.

PART IV

Item 15. Exhibits, Financial Statement Schedules.

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SIGNATURES

Pursuant to the requirements of Section 13 or 15(d) 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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