**UNITED STATESSECURITIES AND EXCHANGE COMMISSION**

**Washington, D.C. 20549**

**FORM 10-K/A**

**(Amendment No. 1)**

(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, 2018or**

**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: 333-207340-04**

**Central Index Key Number of the issuing entity:0001716263**

**UBS Commercial Mortgage Trust2017-C4**

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

** **

**Central Index Key Number of the depositor: 0001532799**

**UBS Commercial MortgageSecuritization Corp.**

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

** **

**Central Index Key Number of the sponsor: 0001685185**

**UBS AG, acting through its branchlocated at 1285 Avenue of the Americas, New York, New York**

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

** **

**Central Index Key Number of the sponsor: 0001238163**

**Société Générale**

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

** **

**Central Index Key Number of the sponsor: 0001541468**

**Ladder Capital Finance LLC**

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

** **

**Central Index Key Number of the sponsor: 0001592182**

**Rialto Mortgage Finance, LLC**

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

** **

**Central Index Key Number of the sponsor: 0001548567**

**CIBC Inc.**

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

** **

**Central Index Key Number of the sponsor: 0001542256**

**Natixis Real Estate Capital 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)** | **38-4046694**

**38-4046695**

**38-7187327**

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

**Identification Number)** |
|------------------------------------------------------------------------------------------------------------|--------------------------------------------------------------------------------------------------|

**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) 713-2000**

Securities registered pursuant to Section 12(b) of theAct:  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 SecuritiesExchange Act of 1934 during the preceding 12 months (or for such shorter periodthat the registrant was required to file such reports), and (2) has beensubject to such filing 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                                                                                         Acceleratedfiler                               o

Non-acceleratedfiler        ⌧ (Do not check if a smaller reporting company)                      Smaller reporting company                        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 ExchangeAct.                               o

Indicate by check mark whether the registrant is a shell company(as defined in Rule 12b-2 of the Act).  oYes ⌧ 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 mostrecently completed 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.

 

 

The sole purpose of this AmendmentNo. 1 to our Annual Report on Form 10-K for the fiscal year ended December 31,2018 filed with the Securities and Exchange Commission on March 25, 2019 (the“Original Form 10-K”) is to replace the report on assessment of compliance andthe accountants’ attestation report of Rialto Capital Advisors, LLC filed asexhibits to the Original Form 10-K under Exhibit 33 and Exhibit 34,respectively, with the corresponding exhibits attached hereto.  Except asdescribed above, no other changes are being made to the Original Form 10-K.

Pursuant to Rule 12b-15 under the Securities Exchange Act of1934, as amended, this Form 10-K/A also contains new certifications pursuant toSection 302 of the Sarbanes-Oxley Act of 2002, which are attached hereto.

**PART IV**

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

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

33          Reports on assessment of compliance with servicing criteria forasset-backed securities.

33.2        Rialto Capital Advisors, LLC, as Special Servicer

33.11       Rialto Capital Advisors, LLC, as Special Servicer ofThe District Mortgage Loan (see Exhibit 33.2) 

33.19       Rialto Capital Advisors, LLC, as Special Servicer ofthe Medirian Sunrise Village Mortgage Loan (see Exhibit 33.2) 

33.27       Rialto Capital Advisors, LLC, as Special Servicer ofthe Bank of America Office Campus Building 600 Mortgage Loan (see Exhibit 33.2)

33.35       Rialto Capital Advisors, LLC, as Special Servicer ofthe DoubleTree Berkeley Marina Mortgage Loan (see Exhibit 33.2) 

33.75       Rialto Capital Advisors, LLC, as Special Servicer of theJW Marriott Chicago Mortgage Loan (see Exhibit 33.2) 

34            Attestationreports on assessment of compliance with servicing criteria for asset-backedsecurities.

34.2        Rialto Capital Advisors, LLC, as Special Servicer

34.11       Rialto Capital Advisors, LLC, as Special Servicer ofThe District Mortgage Loan (see Exhibit 34.2) 

34.19       Rialto Capital Advisors, LLC, as Special Servicer ofthe Medirian Sunrise Village Mortgage Loan (see Exhibit 34.2) 

34.27       Rialto Capital Advisors, LLC, as Special Servicer ofthe Bank of America Office Campus Building 600 Mortgage Loan (see Exhibit 34.2)

34.35       Rialto Capital Advisors, LLC, as Special Servicer ofthe DoubleTree Berkeley Marina Mortgage Loan (see Exhibit 34.2) 

34.75       Rialto Capital Advisors, LLC, as Special Servicer ofthe JW Marriott Chicago Mortgage Loan (see Exhibit 34.2) 

 

**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.

UBS Commercial MortgageSecuritization Corp.(Depositor)

/s/Nicholas Galeone

NicholasGaleone, President

(senior officer in charge ofsecuritization of the depositor)

Date: October 28, 2019

/s/ DavidSchell

DavidSchell, Managing Director

Date: October 28, 2019