UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM SD

SPECIALIZED DISCLOSURE REPORT

PDF SOLUTIONS, INC.

(Exact name of registrant as specified in its charter)

Adnan Raza (408) 280-7900

(Name and telephone number, including area code, of the person to contact

in connection with this report)

Check the appropriate box to indicate the rule pursuant to which this form is being filed, and provide the period to which the information in this form applies:

☒ Rule 13p-1 under the Securities Exchange Act (17 CFR 240.13p-1) for the reporting period from January 1 to December 31, 2020.

Item 1.01. Conflict Minerals Disclosure and Report

PDF Solutions provides comprehensive data solutions designed to empower organizations across the semiconductor ecosystem to improve the yield and quality of their products and operational efficiency for increased profitability. Our products and services include proprietary software, physical intellectual property for integrated circuit designs, electrical measurement equipment, proven methodologies, and professional services. The key benefits of our offerings are greatly improved data connectivity, collection and management, equipment control, and analytics. The company’s products and services are used by Fortune 500 companies across the semiconductor ecosystem to achieve smart manufacturing goals by connecting and controlling equipment, collecting data generated during manufacturing and test operations, and performing advanced analytics and machine learning to enable profitable, high-volume manufacturing. As part of its solutions, the Company develops on-chip instruments that are inserted into test and product wafers and measured on one of two proprietary hardware tools: the pdFasTest® parallel, electrical tester or the eProbe® non-contact, e-beam tool. These tools are installed and used in manufacturing facilities in the United States, Europe, and Asia.

This Specialized Disclosure Form (“Form SD”) and a copy of PDF’s Conflict Minerals Report (filed as Exhibit 1.01 hereto) are being posted to the publicly available Internet site www.pdf.com upon the filing of this Form SD.

Item 1.02 Exhibits

PDF Solutions’ Conflict Minerals Report is attached hereto as Exhibit 1.01.

Item 2.01. Exhibits

The following exhibit is filed as part of this report:

Exhibit 1.01 – Conflict Minerals Report as required by Items 1.01 and 1.02 of this Form.

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 duly authorized undersigned.

Dated: May 26, 2021