"The Texas Rangers have been in violation of baseball’s collective-bargaining agreement since at least last season for failing to pay $39.55 million into a deferred compensation fund, according to a letter sent on Oct. 22, 2009, by MLB executive vice president Rob Manfred to the bidders …"

Rest of story is pay-walled: http://sportsbusinessjournal.com/index.cfm?fuseaction=article.preview&articleid=64832

Also, per @dkaplanSBJ, the story's author:

"Union has agreed to stand down and let new owner cure issue; problem is creditors could torpedo sale"

and

"Other aspect to consider is MLB gave Rgrs a competitive advtg last season; rangers owed $40 mln, so had more $s for payroll"