**UNITED STATESSECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 10-K**

(Mark One)

**x****  ANNUAL REPORT PURSUANT TO SECTION13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**

**For the fiscal year ended December 31, 2019or**

**o**** ****TRANSITIONREPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**

**For the transition period from _____ to _____Commission file number of the issuing entity: 333-206703-01**

**Central Index Key Number of the issuing entity:0001655153**

**CSAIL 2015-C4 Commercial MortgageTrust**

**(exact name of the issuing entity as specified in itscharter)**

** **

**Central Index Key Number of the depositor: 0000802106**

**Credit Suisse First Boston MortgageSecurities Corp.**

**(exact name of the depositor as specified in its charter)**

** **

**Central Index Key Number of the sponsor: 0001628601**

**Column Financial, Inc.**

**(exact name of the sponsor as specified in its charter)**

** **

**Central Index Key Number of the sponsor: 0001632269**

**Benefit Street Partners CRE FinanceLLC**

**(exact name of the sponsor as specified in its charter)**

** **

**Central Index Key Number of the sponsor: 0001666643**

**Walker & Dunlop CommercialProperty Funding I CS, LLC**

**(exact name of the sponsor as specified in its charter)**

** **

**Central Index Key Number of the sponsor: 0001505494**

**The Bancorp Bank**

**(exact name of the sponsor as specified in its charter)**

** **

**Central Index Key Number of the sponsor: 0001576832**

**MC-Five Mile Commercial MortgageFinance LLC**

**(exact name of the sponsor as specified in its charter)**

** **

| **New York****(State or other jurisdiction of  incorporation or organization of**

**the issuing entity)** | **38-3984607**

**38-3984608**

**(I.R.S. Employer**

**Identification Numbers)** |
|------------------------------------------------------------------------------------------------------------|-----------------------------------------------------------------------------------|

**c/o Wells Fargo Bank, National Association**

**as Certificate Administrator**

**9062 Old Annapolis Road**

**Columbia, MD**

**(Address of principalexecutive offices of the issuing entity)**

**21045**

**(Zip Code)**

**Registrant’s telephone number,including area code:**

**(212) 272-6858**

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

| Title of each class | Trading Symbol(s) | Name of each exchange  on which registered |
|---------------------|-------------------|--------------------------------------------|
| None                |              |                                       |

Securities registered pursuant to Section 12(g) of theAct:  None.

Indicate by check mark if the registrant is a well-knownseasoned issuer, as defined in Rule 405 of the Securities Act.  o Yes ⌧No

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

Indicate by check mark whether the registrant (1) has filedall reports required to be filed by Section 13 or 15(d) of the Securities ExchangeAct of 1934 during the preceding 12 months (or for such shorter period that theregistrant was required to file such reports), and (2) has been subject to suchfiling requirements for the past 90 days.  ⌧Yes oNo

Indicate by check mark whether the registrant has submittedelectronically and posted on its corporate Web site, if any, every InteractiveData File required to be submitted and posted pursuant to Rule 405 ofRegulation S-T (Section 232.405 of this chapter) during the preceding 12 months(or for such shorter period that the registrant was required to submit and postsuch files).

Not applicable.

Indicate by check mark if disclosure of delinquent filerspursuant to Item 405 of Regulation S-K (Section 229.405 of this chapter) is notcontained herein, and will not be contained, to the best of registrant’sknowledge, in definitive proxy or information statements incorporated byreference in Part III of this Form 10-K or any amendment to this Form10-K.   

Not applicable.

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

Large accelerated filer       o                                       Accelerated filer                                                                        o

Non-acceleratedfiler         ⌧  (Do not check if a smaller reportingcompany)                                       Smaller reportingcompany                                                        o

                                                                              Emerging growthcompany                                                        o

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

Indicate by check mark whether the registrant is a shellcompany (as defined in Rule 12b-2 of the Act).  o Yes ⌧ No

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

Not applicable.

Indicate by check mark whether the registrant has filed alldocuments and reports required to be filed by Section 12, 13 or 15(d) of theSecurities Exchange Act of 1934 subsequent to the distribution of securitiesunder a plan confirmed by a court.  oYes oNo

Not applicable.

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

Not applicable.

**DOCUMENTS INCORPORATED BY REFERENCE**

** **

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

Not applicable.

 

** **

**EXPLANATORY NOTES**

The Exhibit Index describesexhibits provided by certain parties (in their capacities indicated on theExhibit Index) with respect to the Arizona Grand Resort & Spa MortgageLoan, which constituted approximately 4.8% of the asset pool of the issuingentity as of its cut-off date.  The Arizona Grand Resort & SpaMortgage Loan is an asset of the issuing entity and is part of a loancombination that includes the Arizona Grand Resort & Spa Mortgage Loan andone other *pari passu* loan, which is not an asset of the issuing entity.The other *pari passu* portion of the loan combination was securitized inthe CSAIL 2015-C3 Commercial Mortgage Trust transaction, Commission File Number333-199921-03 (the “CSAIL 2015-C3 Transaction”). This loan combination,including the Arizona Grand Resort & Spa Mortgage Loan, is being servicedand administered pursuant to the pooling and servicing agreement for the CSAIL2015-C3 Transaction, which is incorporated by reference as Exhibit 4.2 to thisAnnual Report on Form 10-K.

The master servicer of a poolingand servicing agreement or trust and servicing agreement also functions as theprimary servicer of the related mortgage loans serviced and administeredpursuant to such agreement unless a separate primary servicer is identifiedherein.  If this report does not identify a separate primary servicer, theservicer compliance statement provided by the master servicer under any suchagreement also encompasses its responsibilities as primary servicer of therelated mortgage loan or mortgage loans.

Wells Fargo Bank, National Association is the custodian ofthe mortgage loans serviced under the Pooling and Servicing Agreement and theArizona Grand Resort & Spa Mortgage Loan.  As a result, Wells FargoBank, National Association is a servicing function participant in thecapacities described above, because it is servicing mortgage loans thatconstituted 5% or more of the assets of the issuing entity as of its cut-offdate. The assessments of compliance with applicable servicing criteria andaccountants’ attestation reports delivered by Wells Fargo Bank, NationalAssociation in the capacities described above are listed in the Exhibit Index.

Midland Loan Services, a Divisionof PNC Bank, National Association is the special servicer of the mortgage loansserviced under the Pooling and Servicing Agreement and the primary servicer ofthe Arizona Grand Resort & Spa Mortgage Loan. As a result, Midland LoanServices, a Division of PNC Bank, National Association is a “servicer” asdefined in Item 1108(a)(2)(iii) of Regulation AB, in the capacities describedabove, because it is servicing mortgage loans that constituted 10% or more ofthe assets of the issuing entity as of its cut-off date. The assessments ofcompliance with applicable servicing criteria, accountants’ attestation reportsand servicer compliance statements delivered by Midland Loan Services, aDivision of PNC Bank, National Association in the capacities described aboveare listed in the Exhibit Index.

Pentalpha Surveillance LLC is the operating advisor of themortgage loans serviced under the Pooling and Servicing Agreement and theArizona Grand Resort & Spa Mortgage Loan.  As a result, PentalphaSurveillance LLC is a servicing function participant in the capacitiesdescribed above, because it is servicing mortgage loans that constituted 5% ormore of the assets of the issuing entity as of its cut-off date. Theassessments of compliance with applicable servicing criteria and accountants’attestation reports delivered by Pentalpha Surveillance LLC in the capacitiesdescribed above are listed in the Exhibit Index.

Wilmington Trust, NationalAssociation acts as trustee of the mortgage loans serviced under the Poolingand Servicing Agreement.  Pursuant to the Pooling and Servicing Agreement,the trustee is required to provide an assessment of compliance with applicableservicing criteria solely with respect to Item 1122(d)(2)(iii) of Regulation AB(regarding advances of funds or guarantees regarding collections, cash flows ordistributions, and any interest or other fees charged for such advances, aremade, reviewed and approved as specified in the transaction agreements).However, during the reporting period, the trustee did not perform any servicingfunction with respect to the servicing criteria specified in Item1122(d)(2)(iii) of Regulation AB.  The master servicer or the specialservicer, to the extent required, performed the servicing function identifiedwith respect to Item 1122(d)(2)(iii) of Regulation AB, and each such partyincluded Item 1122(d)(2)(iii) of Regulation AB in the assessment of compliancewith applicable servicing criteria and accountant’s attestation report for thesubject transaction.  As a result, this Annual Report on Form 10-K doesnot include an assessment of compliance with applicable servicing criteria ofthe trustee. One or more other servicers of the mortgage loans serviced underthe Pooling and Servicing Agreement have delivered one or more assessments ofcompliance with respect to Item 1122(d)(2)(iii) of Regulation AB.

Wells Fargo Bank, NationalAssociation acts as trustee of the Arizona Grand Resort & Spa MortgageLoan.  Pursuant to the pooling and servicing agreement for the CSAIL2015-C3 transaction, the trustee is required to provide an assessment ofcompliance with applicable servicing criteria solely with respect to Item1122(d)(2)(iii) of Regulation AB (regarding advances of funds or guaranteesregarding collections, cash flows or distributions, and any interest or otherfees charged for such advances, are made, reviewed and approved as specified inthe transaction agreements). However, during the reporting period, the trusteedid not perform any servicing function with respect to the servicing criteriaspecified in Item 1122(d)(2)(iii) of Regulation AB.  The master serviceror the special servicer, to the extent required, performed the servicingfunction identified with respect to Item 1122(d)(2)(iii) of Regulation AB, andeach such party included Item 1122(d)(2)(iii) of Regulation AB in theassessment of compliance with applicable servicing criteria and accountant’sattestation report for the subject transaction.  As a result, this AnnualReport on Form 10-K does not include an assessment of compliance withapplicable servicing criteria of the trustee. One or more other servicers ofthe Arizona Grand Resort & Spa Mortgage Loan have delivered one or moreassessments of compliance with respect to Item 1122(d)(2)(iii) of RegulationAB.

This Annual Report on Form 10-K includesassessments of compliance with applicable servicing criteria and accountants’attestation reports from CoreLogic Commercial Real Estate Services, Inc. andNational Tax Search, LLC.  These entities were engaged by the masterservicer under the Pooling and Servicing Agreement to remit tax paymentsreceived from the escrow accounts of borrowers to local taxing authorities, toreport tax amounts due, to verify tax parcel information, and to verifynon-escrow tax payments. These servicing functions are included within theservicing criteria set forth in Items 1122(d)(4)(xi) and 1122(d)(4)(xii) ofRegulation AB.  Therefore, under the principles-based definition of“servicer” set forth in Item 1101(j) of Regulation AB that looks to thefunctions that an entity performs, these vendors are “servicers” for thepurposes of Item 1122 of Regulation AB.  *See* Compliance andDisclosure Interpretations, Section 301.01 (Item 1101(j)).

Theassessment of compliance with applicable servicing criteria, accountants’attestation report and servicer compliance statement of the certificateadministrator of the Arizona Grand Resort & Spa Mortgage Loan listed on theExhibit Index is omitted from this Annual Report on Form 10-K as thecertificate administrator pursuant to the related pooling and servicingagreement or trust and servicing agreement does not perform any activities thataddress servicing criteria with respect to the issuing entity and because it isnot a “servicer” that meets the criteria in Item 1108(a)(2)(i) through (iii) ofRegulation AB.

With respect to the *pari passu*loan combination that includes the Arizona Grand Resort & Spa MortgageLoan, (i) the report on assessment of compliance with servicing criteria andattestation report on assessment of compliance with servicing criteria ofRialto Capital Advisors, LLC as special servicer of the Arizona Grand Resort& Spa Mortgage Loan, listed on the Exhibit Index are omitted from thisAnnual Report on Form 10-K as they are not required to be included on this AnnualReport on Form 10-K per Instruction 3 to Item 1122 of Regulation AB because itis a party performing activities that address servicing criteria relating to 5%or less of the assets of the issuing entity; and (ii) the servicer compliancestatement of Rialto Capital Advisors, LLC as special servicer of the ArizonaGrand Resort & Spa Mortgage Loan, listed on the Exhibit Index is omittedfrom this Annual Report on Form 10-K as it is not required by Item 1123 ofRegulation AB to be included on this Annual Report on Form 10-K because it isan unaffiliated party that is not a “servicer” that meets the criteria in Item1108(a)(2)(i) through (iii) of Regulation AB.

**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 ofFinancial Condition and Results of Operations.**

Omitted.

**Item 7A.  Quantitative and Qualitative DisclosuresAbout Market Risk.**

Omitted.

**Item 8.  Financial Statements and Supplementary Data.**

Omitted.

**Item 9.  Changes in and Disagreements WithAccountants 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 CorporateGovernance.**

Omitted.

**Item 11.  Executive Compensation.**

Omitted.

**Item 12.  Security Ownership of Certain BeneficialOwners and Management and Related Stockholder Matters.**

Omitted.

**Item 13.  Certain Relationships and RelatedTransactions, and Director Independence.**

Omitted.

**Item 14.  Principal Accounting Fees and Services.**

Omitted.

**ADDITIONAL DISCLOSURE ITEMS FOR REGULATION AB**

**Item 1112(b) of Regulation AB, Significant ObligorFinancial Information.**

 

The Fairmont Orchid Mortgage Loan (Loan # 1 on Annex A of theprospectus supplement of the registrant relating to the issuing entity filed onNovember 25, 2015 pursuant to Rule 424(b)(5)) constitutes a significant obligorwithin the meaning of Item 1101(k)(2) of Regulation AB as disclosed in theprospectus supplement. In accordance with Item 1112(b) of Regulation AB, themost recent unaudited net operating income of the significant obligor was$21,622,921.00 for the twelve- month period ended December 31, 2019.

**Item 1114(b)(2) of Regulation AB, Significant EnhancementProvider Financial Information.**

No entity or group of affiliated entities provides any external creditenhancement or other support for the certificates within this transaction asdescribed under Item 1114(a) of Regulation AB.

**Item 1115(b) of Regulation AB, Certain DerivativesInstruments (Financial Information).**

No entity or group of affiliated entities provides anyderivative instruments or other support for the certificates within this transactionas described under Item 1115 of Regulation AB.

**Item 1117 of Regulation AB, Legal Proceedings.**

The registrant knows of no material pending legal proceedinginvolving the trust or any party related to the trust, other than routinelitigation incidental to the duties of those respective parties, and thefollowing, with respect to Wells Fargo Bank, National Association, ascertificate administrator, as custodian and as trustee.

Beginning on June 18, 2014, a group of institutionalinvestors filed civil complaints in the Supreme Court of the State of New York,New York County, and later the U.S. District Court for the Southern District ofNew York, against Wells Fargo Bank, N.A., (“Wells Fargo Bank”) in itscapacity as trustee for certain residential mortgage backed securities (“RMBS”)trusts.  The complaints against Wells Fargo Bank alleged that the trusteecaused losses to investors and asserted causes of action based upon, amongother things, the trustee's alleged failure to: (i) notify and enforce repurchaseobligations of mortgage loan sellers for purported breaches of representationsand warranties, (ii) notify investors of alleged events of default, and (iii)abide by appropriate standards of care following alleged events of default.Relief sought included money damages in an unspecified amount, reimbursement ofexpenses, and equitable relief. In November 2018, Wells Fargo Bank reached anagreement, in which it denied any wrongdoing, to resolve such claims on aclasswide basis for the 271 RMBS trusts at issue.  On May 6, 2019, thecourt entered an order approving the settlement agreement.  Separatelawsuits against Wells Fargo Bank making similar allegations filed by certainother institutional investors concerning several RMBS trusts in New Yorkfederal and state court are not covered by the agreement.  With respect tosuch litigations, Wells Fargo Bank believes plaintiffs' claims are withoutmerit and intends to contest the claims vigorously, but there can be noassurances as to the outcome of the litigations or the possible impact of thelitigations on Wells Fargo Bank or the RMBS trusts.

**Item 1119 of Regulation AB, Affiliations and CertainRelationships and Related Transactions.**

The information regarding this Item has been previously providedin a prospectus supplement of the Registrant relating to the issuing entityfiled on November 25, 2015 pursuant to Rule 424(b)(5).

**Item 1122 of Regulation AB, Compliance with ApplicableServicing Criteria.**

The reports on assessments of compliance with the servicingcriteria for asset-backed securities and related attestation reports on suchassessments of compliance with respect to the mortgage loans are attachedhereto under Item 15 to this Annual Report on Form 10-K. Attached as Exhibit Oto the Pooling and Servicing Agreement incorporated by reference as Exhibit 4.1to this Annual Report on Form 10-K is a chart identifying the entitiesparticipating in a servicing function for the transaction responsible for eachapplicable servicing criteria set forth in Item 1122(d).

The reports on assessments of compliance with the servicingcriteria for asset-backed securities and related attestation reports on suchassessments of compliance with respect to the Arizona Grand Resort & SpaMortgage Loan, which is being serviced and administered pursuant to the poolingand servicing agreement for the CSAIL 2015-C3 Transaction, are attached heretounder Item 15 to this Annual Report on Form 10-K. Attached as Exhibit O to thepooling and servicing agreement for the CSAIL 2015-C3 Transaction incorporatedby reference as Exhibit 4.2 to this Annual Report on Form 10-K is a chartidentifying the entities participating in a servicing function for the CSAIL2015-C3 Transaction responsible for each applicable servicing criteria setforth in Item 1122(d).

The report on assessment of compliance with applicableservicing criteria furnished pursuant to Item 1122 of Regulation AB by MidlandLoan Services, a Division of PNC Bank National Association (“Midland”)discloses that a material instance of noncompliance occurred, as describedbelow:

Material Instance of Noncompliance

In certain instances, the ScheduleAL Files (Item 1125 of Regulation AB) were not reported in accordance with theterms specified in the transaction agreements, in conflict with Item1122(d)(3)(i): “Reports to investors, including those to be filed with theCommission, are maintained in accordance with the transaction agreements andapplicable Commission requirements. Specifically, such reports: (A) Are preparedin accordance with timeframes and other terms set forth in the transactionagreements”.  The noncompliance consisted of omitted or inaccuratelyreported fields as described in (1) and (2) below.  (1) In connection withother enhancements Midland made to its manual Schedule AL process, starting inApril 2019, Midland developed and implemented new Schedule AL reportingtemplates for each applicable CMBS transaction that closed prior to April 2019and for each applicable CMBS transaction going forward.  Related to this,Midland made certain template setup errors, along with related and other manualinputting of information errors, and the errors were not identified prior tosubmission of the applicable Schedule AL Files in certain cases due tobreakdowns in quality control.  (2) In one applicable transaction, therelated Schedule AL File for a given month was not saved properly resulting inthe prior month's Schedule AL File being submitted for the given month insteadof the correct Schedule AL File. 

The identified instances did notinvolve the servicing of assets included in this securitization.

Steps Taken to Remedy the Material Instance of Noncompliance

Midland’s Schedule AL reportingprocess was enhanced in April of 2019, however, the process remained manualthroughout the 2019 calendar year.  Errors relating to certain Schedule ALFiles during 2019 were identified during the related audit.  Followingidentification, Midland made staffing changes and additional enhancements andimprovements to its processes and procedures to support its Schedule ALreporting obligations and expects to move to an automated solution for thisprocess.  

Midland is currently remediating theSchedule AL reporting for certain of the CMBS transactions found to beincorrect.

**Item 1123 of Regulation AB, Servicer Compliance Statement.**

The servicer compliance statements are attached as Exhibitsto this Annual Report on Form 10-K.

**PART IV**

**Item 15. Exhibits, Financial Statement Schedules**

(a)         The following is a list of documents filed as part of this Annual Report onForm 10-K:

(1)         Not applicable

(2)         Not applicable

(3)         See below

 

4.1          Poolingand Servicing Agreement, dated as of November 1, 2015, by and among CreditSuisse First Boston Mortgage Securities Corp., as Depositor, Wells Fargo Bank,National Association, as Master Servicer, Midland Loan Services, a Division ofPNC Bank, National Association, as Special Servicer, Pentalpha SurveillanceLLC, as Operating Advisor, Wells Fargo Bank, National Association, asCertificate Administrator and Wilmington Trust, National Association, asTrustee (filed as Exhibit 4.1 to the registrant’s Current Report on Form 8-Kfiled on November 25, 2015 under Commission File No. 333-206703-01 andincorporated by reference herein)

4.2          Poolingand Servicing Agreement, dated as of August 1, 2015, by and among Credit SuisseFirst Boston Mortgage Securities Corp., as Depositor, Midland Loan Services, aDivision of PNC Bank, National Association, as Master Servicer, Rialto CapitalAdvisors, LLC, as Special Servicer, Pentalpha Surveillance LLC, as OperatingAdvisor, Wells Fargo Bank, National Association, as Certificate Administratorand Wells Fargo Bank, National Association, as Trustee (filed as Exhibit 4.2 tothe registrant’s Current Report on Form 8-K filed on November 25, 2015 underCommission File No. 333-206703-01 and incorporated by reference herein)

4.3          Co-LenderAgreement, dated as of August 18, 2015, by and among Column Financial, Inc., asInitial Note A-1 Holder and Column Financial, Inc., as Initial Note A-2 Holder(filed as Exhibit 4.3 to the registrant’s Current Report on Form 8-K filed onNovember 25, 2015 under Commission File No. 333-206703-01 and incorporated byreference herein)

31          Rule 13a-14(d)/15d-14(d)Certifications.

33          Reports on assessment of compliance with servicing criteria for asset-backedsecurities.

33.1       Wells Fargo Bank, NationalAssociation, as Master Servicer

33.2       Midland Loan Services, aDivision of PNC Bank, National Association, as Special Servicer

33.3       Wilmington Trust, National Association, as Trustee (Omitted. See ExplanatoryNotes.)

33.4       Wells Fargo Bank, NationalAssociation, as Certificate Administrator

33.5       Wells Fargo Bank, NationalAssociation, as Custodian

33.6       Pentalpha SurveillanceLLC, as Operating Advisor

33.7       CoreLogic Commercial RealEstate Services, Inc., as Servicing Function Participant

33.8       National Tax Search, LLC,as Servicing Function Participant

33.9       Midland Loan Services, aDivision of PNC Bank, National Association, as Primary Servicer of the ArizonaGrand Resort & Spa Mortgage Loan (see Exhibit 33.2)

33.10     Rialto Capital Advisors, LLC, as Special Servicer of the Arizona Grand Resort& Spa Mortgage Loan (Omitted. See Explanatory Notes.)

33.11     Wells Fargo Bank, National Association, as Trustee of the Arizona Grand Resort& Spa Mortgage Loan (Omitted. See Explanatory Notes.)

33.12     Wells Fargo Bank, NationalAssociation, as Custodian of the Arizona Grand Resort & Spa Mortgage Loan(see Exhibit 33.5)

33.13     Pentalpha SurveillanceLLC, as Operating Advisor of the Arizona Grand Resort & Spa Mortgage Loan(see Exhibit 33.6)

34          Attestation reports onassessment of compliance with servicing criteria for asset-backed securities.

34.1       Wells Fargo Bank, NationalAssociation, as Master Servicer

34.2       Midland Loan Services, aDivision of PNC Bank, National Association, as Special Servicer

34.3       Wilmington Trust, National Association, as Trustee (Omitted. See ExplanatoryNotes.)

34.4       Wells Fargo Bank, NationalAssociation, as Certificate Administrator

34.5       Wells Fargo Bank, NationalAssociation, as Custodian

34.6       Pentalpha SurveillanceLLC, as Operating Advisor

34.7       CoreLogic Commercial RealEstate Services, Inc., as Servicing Function Participant

34.8       National Tax Search, LLC,as Servicing Function Participant

34.9       Midland Loan Services, a Divisionof PNC Bank, National Association, as Primary Servicer of the Arizona GrandResort & Spa Mortgage Loan (see Exhibit 34.2)

34.10     Rialto Capital Advisors, LLC, as Special Servicer of the Arizona Grand Resort& Spa Mortgage Loan (Omitted. See Explanatory Notes.)

34.11     Wells Fargo Bank, National Association, as Trustee of the Arizona Grand Resort& Spa Mortgage Loan (Omitted. See Explanatory Notes.)

34.12     Wells Fargo Bank, NationalAssociation, as Custodian of the Arizona Grand Resort & Spa Mortgage Loan(see Exhibit 34.5)

34.13     Pentalpha SurveillanceLLC, as Operating Advisor of the Arizona Grand Resort & Spa Mortgage Loan(see Exhibit 34.6)

35          Servicer compliance statements.

35.1       Wells Fargo Bank, NationalAssociation, as Master Servicer

35.2       Midland Loan Services, aDivision of PNC Bank, National Association, as Special Servicer

35.3       Wells Fargo Bank, NationalAssociation, as Certificate Administrator

35.4       Midland Loan Services, aDivision of PNC Bank, National Association, as Primary Servicer of the ArizonaGrand Resort & Spa Mortgage Loan (see Exhibit 35.2)

35.5       Rialto Capital Advisors, LLC, as Special Servicer of the Arizona Grand Resort& Spa Mortgage Loan (Omitted. See Explanatory Notes.)

99.1       MortgageLoan Purchase Agreement, dated as of November 1, 2015, between Credit SuisseFirst Boston Mortgage Securities Corp. and Column Financial, Inc. (filed asExhibit 99.1 to the registrant’s Current Report on Form 8-K filed on November25, 2015 under Commission File No. 333-206703-01 and incorporated by referenceherein)

99.2       MortgageLoan Purchase Agreement, dated as of November 1, 2015, between Credit SuisseFirst Boston Mortgage Securities Corp. and Benefit Street Partners CRE FinanceLLC (filed as Exhibit 99.2 to the registrant’s Current Report on Form 8-K filedon November 25, 2015 under Commission File No. 333-206703-01 and incorporatedby reference herein)

99.3       MortgageLoan Purchase Agreement, dated as of November 1, 2015, among Credit SuisseFirst Boston Mortgage Securities Corp., Walker & Dunlop Commercial PropertyFunding I CS, LLC and Walker & Dunlop Commercial Property Funding, LLC(filed as Exhibit 99.3 to the registrant’s Current Report on Form 8-K filed onNovember 25, 2015 under Commission File No. 333-206703-01 and incorporated byreference herein)

99.4       MortgageLoan Purchase Agreement, dated as of November 1, 2015, between Credit SuisseFirst Boston Mortgage Securities Corp. and The Bancorp Bank (filed as Exhibit99.4 to the registrant’s Current Report on Form 8-K filed on November 25, 2015under Commission File No. 333-206703-01 and incorporated by reference herein)

99.5       MortgageLoan Purchase Agreement, dated as of November 1, 2015, between Credit SuisseFirst Boston Mortgage Securities Corp. and MC-Five Mile Commercial MortgageFinance LLC (filed as Exhibit 99.5 to the registrant’s Current Report on Form8-K filed on November 25, 2015 under Commission File No. 333-206703-01 andincorporated by reference herein)

(b)         The exhibits required to be filed by the Registrant pursuant to Item 601 ofRegulation S-K are listed above.

(c)         Not Applicable.

 

**SIGNATURES**

Pursuant to the requirements of Section 13 or 15(d) of theSecurities Exchange Act of 1934, the registrant has duly caused this report tobe signed on its behalf by the undersigned, thereunto duly authorized.

Credit Suisse First Boston MortgageSecurities Corp.(Depositor)

/s/ OliverNisenson

OliverNisenson, Director

(senior officer in charge ofsecuritization of the depositor)

Date: March 16, 2020