Five British Beer & Pub Association (BBPA) members have still not formally submitted codes of practice to the BII - more than eight months since the official deadline passed.
Despite the BBPA promising all its members would have their new codes finalised by last June, there are still companies dragging their feet.
Some sources suggest it is a reaction from small pubcos over their frustration at the perceived abuse of the tie by larger companies.
The five companies are Harveys, Camerons, Gray & Sons, Holden's and Felinfoel.
However, the BII confirmed Holden's had submitted a draft code for comment.
The 21-strong committee has been accrediting the codes since last year in an effort to make it clear to prospective and current tenants what their responsibilities are in running a pub.
Hamish Elder, Harveys' joint managing director, admitted to The Publican: "We are dragging our feet terribly. We have something in the pipeline and it is with our solicitors."
He added: "There's a large degree of difference between a company like us and people who have long leases."
John Foots, Camerons' financial director, said: "We are very nearly there, it's in its final form. We expect to have it accredited by the end of March."
Bernard Brindley, deputy chairman of the benchmarking committee, said: "If they (companies) do not put a code forward it's down to the BBPA to talk to its members. It's the BBPA's problem, not the BII's, we are just there to accredit the codes."
Brigid Simmonds, chief executive of the British Beer Association said: "We have done our best to help all our members.
"We are helping the last few to get over the line. It was always about the big companies getting codes. For smaller companies, it's more difficult as they have different ways of working."
The BBPA said 99 per cent of its members' pubs are now covered by a code.