1934 Act Registration No. 1-14700

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

FORM 6-K

REPORT OF FOREIGN PRIVATE ISSUER

PURSUANT TO RULE 13a-16 OR 15d-16

OF THE SECURITIES EXCHANGE ACT OF 1934

For the month of January 2019

Taiwan Semiconductor Manufacturing Company Ltd.

(Translation of Registrant’s Name Into English)

No. 8, Li-Hsin Rd. 6,

Hsinchu Science Park,

Taiwan

(Address of Principal Executive Offices)

(Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.)

Form 20-F  ☒            Form 40-F  ☐

(Indicate by check mark whether the registrant by furnishing the information contained in this form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.)

Yes  ☐            No  ☒

(If “Yes” is marked, indicated below the file number assigned to the registrant in connection with Rule 12g3-2(b): 82:            .)

SIGNATURES

Pursuant to the requirements 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.

Clarification of media reports

TSMC has discovered that a shipment of certain chemical used in the manufacturing process deviated from specifications and caused wafers to have lower yields. We are carefully investigating the root cause and are communicating with affected customers regarding remedial actions.

We estimate that most of the affected wafers can be made up in the First Quarter, with the remainder made up in the Second Quarter. Based on our current estimate, TSMC should be able to meet its First Quarter guidance given on January 17, 2019.