After providing $140 million in litigation financing to Sysco Corp. for price-fixing cases against pork, beef and chicken companies, Burford Capital exercised its contractual right to veto settlement offers that Sysco wanted to accept. Then as part of a settlement of its fight with Burford, Sysco assigned the antitrust claims to a Burford affiliate, Carina Ventures, and joined in Carina’s motions to substitute as plaintiff.Rejecting the requests in the pork and beef litigation — as an exercise of discretion under Federal …