A Texas lawyer whose $4.1 million payment from Labaton Sucharow is at the heart of a special master’s inquiry has worked with the New York plaintiffs firm in at least three other high profile litigation matters, according to declarations submitted last week.

Labaton partners Christopher Keller and Eric Belfi filed the declarations in response to an Oct. 16 order by Judge Mark Wolf of the U.S. District Court for the District of Massachusetts asking for more information into the firm’s relationship with Houston lawyer Damon Chargois. Wolf is considering whether to approve a deal struck earlier this month between Labaton and special master Gerald Rosen, whose investigation into potential overbilling revealed that Labaton had failed to disclose what he called a $4.1 million referral payment to Chargois. The Houston lawyer had ties to the lead plaintiff in the State Street case, Arkansas Teacher Retirement System.