A spokesman for the Menil Collection said that restoration work on Picasso's "Woman in a Red Armchair" has been "going very well" and the damage appears to have been caught in time.
The vandalism of the 1929 painting on June 13 was caught on cellphone video. The painting was doused with gold spray paint in the image of a bull and the word "CONQUISTA" according to police.
The vandal fled the scene immediately after the incident. Houston police are still investigating, but no charges have been filed in the case.
The Associated Press contributed to this report.