EXHIBIT 99.1
EXHIBIT A
JOINT FILING AGREEMENT
(Pursuant to Rule 13d-1(f)(1) under the Securities Exchange Act of 1934, as
amended)
Each of the undersigned hereby agrees to be included in the filing
of the Amendment No. 1 to Schedule 13D dated December 20, 1999 and any
subsequent amendments hereto, relating to the Common Stock, $0.0001 par value
per share, of Mannatech, Incorporated, a Texas corporation, beneficially
owned by each of the undersigned.
December 20, 1999
/s/ XXXXXX X. XXXXXX /s/ HARLEY XXXXXXXX XXXXXXXX, XX., M.D.
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XXXXXX X. XXXXXX HARLEY XXXXXXXX XXXXXXXX, XX., M.D.
/s/ XXXXXXX X. XXXXXXXX /s/ XXXX XXXXXXX, XX.
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XXXXXXX X. XXXXXXXX XXXX XXXXXXX, XX.
THE XXXXXXXX FAMILY PARTNERSHIP
By: /s/ XXXXXXX X. XXXXXXXX /s/ XXXXX XXXXXXX
----------------------- --------------------------------------
Xxxxxxx X. Xxxxxxxx, XXXXX XXXXXXX
its General Partner
/s/ XXXXXXX X. XXXXXXXX /s/ XXXXXX XXX XXXXXXX, XX.
---------------------------- --------------------------------------
XXXXXXX X. XXXXXXXX XXXXXX XXX XXXXXXX, XX.
/s/ XXXXXX X. XXXXXXX
----------------------------
XXXXXX X. XXXXXXX
