from SC 13D/A 1 page Joint Filing Agreement Pursuant to and in Accordance With Rule 13d-1(k)(1) Under the Securities Exchange Act of 1934, the Undersigned Hereby Agree to Jointly File the Schedule 13d/a Dated May 12, 2000 and Any Amendments Thereto With Respect to the Beneficial Ownership by Each of the Undersigned of Shares of Common Stock of Impax Laboratories, Inc. Such Joint Filings May Be Executed by One or More of US on Behalf of Each of the Undersigned. This Agreement May Be Executed in Any Number of Counterparts, Each of Which Shall Be Deemed an Original. Executed This 12th Day of May, 2000. Fleming US Discovery Fund III, L.P. By: Fleming US Discovery Partners, L.P., Its General Partner By: Fleming US Discovery, LLC, Its General Partner By: /S/ Robert L. Burr Robert L. Burr, Member Fleming US Discovery Offshore Fund III, L.P. By: Fleming US Discovery Partners, L.P., Its General Partner By: Fleming US Discovery, LLC, Its General Partner By: /S/ Robert L. Burr Robert L. Burr, Member Fleming US Discovery Partners, L.P. By: Fleming US Discovery, LLC, Its General Partner By: /S/ Robert L. Burr Robert L. Burr, Member Fleming US Discovery, LLC By: /S/ Robert L. Burr Robert L. Burr, Member Robert Fleming, Inc. By: /S/ Arthur A. Levy Arthur A. Levy, Director Robert Fleming Holdings, Ltd. By: /S/ Arthur A. Levy Arthur A. Levy, Director

from SC 13D/A ~50 pages Stock Purchase Agreement

from SC 13D/A ~50 pages Stock Purchase Agreement

from SC 13D/A ~20 pages Registration Rights Agreement

from SC 13D/A ~5 pages Amendment No. 1 to Stockholders' Agreement

from SC 13D/A ~5 pages Amendment to Restated Registration Rights Agree.