A number of Lloyd's underwriters have issued a direct challenge to chairman Lord Levene's plans to make them adhere to strict trading rules.
Some Lloyd's underwriters could even quit the market if they found the franchise board's guidelines unacceptable.
One managing director of a Lloyd's underwriter said: "Ultimately it is our capital provider that will determine how we run our business."
He was responding to comments made by Levene in his lecture to Airmic.
Levene said: "Each underwriting business will sign an agreement to abide by a range of standards and guidelines, so that we can protect the Lloyd's brand".
But a managing director of a Lloyd's syndicate countered that venture capitalists backing Lloyd's syndicates may not tolerate excessive interference by the franchise board.
"Though the franchise board is designed to bring the poorer performers in the market to book, the fact is that some of the venture
capitalists backing the market have a better rating than Lloyd's.
"And if they weren't happy with the guidelines being set down by the franchise board they would be able to step out of the market."