As filed with the Securities and Exchange Commission on September 15, 2021

Registration No. 333-259247

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 1

TO

FORM S-1

REGISTRATION STATEMENT

UNDER

THE SECURITIES ACT OF 1933

GREENIDGE GENERATION HOLDINGS INC.

(Exact name of registrant as specified in its charter)

590 Plant Road

Dresden, NY 14441

(315) 536-2359

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Jeffrey E. Kirt

Chief Executive Officer

590 Plant Road

Dresden, NY 14441

(315) 536-2359

(Names, address, including zip code, and telephone number, including area code, of agent for service)

Approximate date of commencement of proposed sale to the public: As soon as practicable after this Registration Statement becomes effective.

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, check the following box.  ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☒

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, 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 comply with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of Securities Act.  ☐

THIS POST-EFFECTIVE AMENDMENT NO. 1 TO S-1 REGISTRATION STATEMENT SHALL BECOME EFFECTIVE UPON FILING WITH THE SEC IN ACCORDANCE WITH RULE 462(d) UNDER THE SECURITIES ACT OF 1933.

EXPLANATORY NOTE

This Post-Effective Amendment No. 1 to Form S-1 Registration Statement (File No. 333-259247) originally filed by Greenidge Generation Holdings Inc. (the “Company”) on September 1, 2021, as amended on September 13, 2021 and declared effective on September 14, 2021 (the “Registration Statement”) is being filed pursuant to Rule 462(d) solely for the purpose of filing Exhibits 2.1 and 10.4 with respect to such Registration Statement. Accordingly, this Amendment consists only of the facing page, this explanatory note, Item 16(a) of Part II of the Registration Statement and the signature page. This Amendment does not modify any other provision of the prospectus contained in Part I or Part II of the Registration Statement.

PART II

INFORMATION NOT REQUIRED IN THE PROSPECTUS

Item 16. Exhibits.

(a) Exhibits.

II-1

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the Town of Torrey, State of New York, on September 15, 2021.

Pursuant to the requirements of the Securities Act of 1933, this registration statement has been signed by the following persons in the capacities and on the dates indicated.