Charges of fraud in government-sponsored research have gotten the headlines, but it's new federal conflict-of-interest rules that are riling the scientific community. Regulations drafted by the National Institutes of Health would require universities to adopt ethics standards that would, among other things, bar scientists from holding certain kinds of stock in companies that hire them to run clinical trials of drugs. The difficulty is that cash-poor small companies often pay scientists in stock. Researchers fear the new rules would stifle drug development. But congressional critics think the NIH hasn't gone far enough. Representative Ted Weiss (D-N. Y.) is pushing for legislation imposing even more stringent conflict-of-interest requirements.