Investors are asking drugmakers to give biosimilars their due. The Wall Street Journal’s Pharmalot blog reports that a group of 19 institutional investors has drawn up a list of business principals, which include not disparaging biosimilars as being inferior to branded biologics.

The spat may appear contradictory in that many manufacturers of biologics already have biosimilar portfolios or are in the process of stocking their pipelines with lookalike drugs, but the manufacturers of branded biologics are doing their best to keep sales of those drugs humming. Among these efforts have been a spate of state proposals that would not allow biosimilars to be swapped for branded biologics at the pharmacy counter—a practice very much in play with generics—as well as lobbying to require that branded biologics and biosimilars have distinct international proprietary names.

Novartis, whose subsidiary Sandoz has been providing biosimliars to global markets, and Amgen have agreed to follow the business principles.

The Journal says the investor group also wants boards “to disclose information about any business deals that would hinder the availability of biosimilars,” such as pay-for-delay arrangements in which generics makers accept a fee to delay a generic rollout.