Here is a Florida case whcih discusses the obligation between attorneys on a fee split, and the difference between an attorney split and a fee owed by the client.  Here, attorney 1 referred the case to attorney 2, and was then terminated.  Result?  Attorney 2 owes a specific percentage to Attorney 1.

"An appellate court has ruled that two Miami lawyers should split a contingency fee award based on their written fee agreement — even though one lawyer was fired by the client on the advice of the other lawyer before the case was won.

A 4th District Court of Appeal panel unanimously ruled April 2 that Scott Jay, who referred a legal malpractice case to Warren Trazenfeld, is entitled to 25 percent of the $218,000 fee Trazenfeld won as part of a $485,000 judgment in Broward Circuit Court in 2003.

Trazenfeld had argued that Jay was not entitled to any fees because he thought that when his client terminated Jay, the fee agreement was voided. Jay’s only claim, he said, was based on quantum meruit, meaning that payment should be based on the reasonable value of services provided. But Jay was not even entitled to that, Trazenfeld said, because Jay had not kept complete time records of his work.

Broward Circuit Judge Robert Lance Andrews agreed with Trazenfeld. But the 4th DCA panel rejected that argument. First, it said case precedent holds that the quantum meruit rule was inapplicable because it applies to the client’s obligation, not to co-counsel’s obligation.

"The written fee agreement provides that co-counsel are jointly owed the fee," the panel wrote. "And because the contract did not specify otherwise, the division of the fee would ordinarily be equal."

The panel also rejected Trazenfeld’s argument about the time records.

"Here, where the fee agreement effectually makes the division, it would serve no purpose to keep such records to establish the share of each," the panel wrote. "In this kind of joint representation, counsel may recognize from the beginning of their undertaking that the amount of time spent by either will not control the division. … As long as such a division is not unreasonable and does not violate the regulatory rules of the Florida Bar, there is no good reason why courts should resort to time records to divide the fee."