Dyadic International Inc (DYAI)

[Paullee]

April 16, 2019
Division of Corporation Finance
U.S. Securities and
Exchange Commission
100 F Street, N.E.
Washington, D.C. 20549
Division of Corporation Finance:
This is to certify that on April 12, 2019
The Nasdaq Stock Market (the "Exchange") received from
Dyadic International, Inc.
(the "Registrant") a copy of the Registrant's application on
Form 8 -A 12(b) for the registration of the following security:

Common Stock, par value $0.001 per share

We further certify that the security described above has been approved by the Exchange for listing and registration.
We understand that the Registrant is seeking immediate acceleration of the effective date of registration, and we hereby join in such request.

Sincerely,

William Slattery, CFA
Vice President
Listing Qualifications