copyright 2009, The Washington Post WASHINGTON -- Since the 1990s, the medical-device industry has been a favorite among aggressive investors. Fueled by a mix of technological advances, venture capital investments and regulatory changes, the industry grew rapidly. Successful devices include everything from the most simple -- tongue depressors and bedpans -- to high-tech stents, heart valves and hip-joint replacements. Industry revenue in the United States doubled over a decade to about $140 billion in 2008, according to Venkat Rajan, a medical industry analyst at Frost & Sullivan. At the same time, the Standard & Poor's health-care equipment index, which includes stocks of medical device companies, increased nearly three times the rate of the broader stock market. The price of Medtronic, a stock owned by several lawmakers, rose from $7 in 1995 to $50 early last year. As with other companies, the stock price has dropped to about $40 because of economic turmoil and questions about the impact of health-care reform. 'It was a go-go time,' Jan Wald, senior medical technology analyst at Noble Financial Group. Wald said the industry received a boost in 1997, when Congress approved the FDA Modernization Act, which streamlined the device approval process at the Food and Drug Administration. The law followed years of industry lobbying. It created a fast-track approval process for many devices. A co-sponsor of the law was Rep. Fred Upton, R-Mich., who the previous year had sponsored legislation making it easier for medical-device companies to export their products. Upton had invested in the medical-device industry before he sponsored those pieces of legislation. He owned stock in Stryker, a medical company based in his district. In the beginning, he held a relatively small amount in two trusts that in 1995 were valued at $2,000 to $30,000, documents show. Over the years, his investment grew, reaching between $350,000 and $750,000. His holdings dropped last year to below $500,000. 'Fred is a proud supporter of Stryker, a locally grown company that has defied the poor business climate in Michigan and developed into a global leader in the medical community,' Upton spokesman Sean Bonyun said. Stryker accounts 'for over 1,600 good-paying jobs in (southwest) Michigan at a time when our state's unemployment hovers at 15 percent.' In a statement, Bonyun said that Upton's transactions are 'a matter of public record and his finances are properly disclosed on an annual basis under the watchful eye' of the ethics committee. About two dozen lawmakers have frequently invested in a constellation of medical-device companies, including industry leaders such as Abbott, Baxter, GE, Johnson & Johnson, Medtronic and Stryker. In addition to Sen. John Kerry, D-Mass., Rep. James Sensenbrenner, R-Wis., and Upton, lawmakers with significant holdings include Sen. Dianne Feinstein, D-Calif., Rep. Jane Harman, D-Calif., Rep. Rodney Frelingthuysen, R-N.J., and Sheldon Whitehouse, D-R.I. The lawmakers' holdings became a backdrop to the health-care debate in September when Sen. Max Baucus, D-Mont., chairman of the Senate Finance Committee, recommended the tax on medical devices as a way of raising about $40 billion over a decade. (After intense lobbying by the industry, Senate Democrats reduced the proposed tax to $20 billion.) The response was swift -- and not only from lawmakers invested in the industry. Senators, representatives and governors in California, Indiana, Minnesota, Massachusetts and other states signed letters to congressional leaders. The Capitol Hill investors also had their say. For example, in addition to releasing a statement, Kerry was among dozens of lawmakers who signed on to one of the letters. 'With such a large number of firms manufacturing as many as 80,000 unique medical device technologies, a one-size fits all excise tax could have significant ramifications for an industry,' the letter said. For his part, Upton joined other House members who signed the letter that Sensenbrenner wrote. 'We urge you to consider the importance of these life-saving technologies as health reform is considered,' said the letter addressed to House Speaker Nancy Pelosi, D-Calif. Kerry and Sensenbrenner said their investments in such companies -- a relatively small proportion of their families' overall holdings -- played no role in their opposition to the proposed tax. They said they are looking out for the economic interests of their states, both of which have become bastions of the medical device industry, along with the well-being of Americans. Through a spokeswoman, Kerry, whose net worth for 2008 was listed as $159 million to $259 million, said that virtually all of the medical-device holdings are in trusts controlled by his wife or in family trusts that he inherited. Spokeswoman Jodi Seth said the inherited holdings 'are managed by a trustee who is a member of a private wealth-management firm.' 'It's ridiculous to suggest that inherited trusts that he doesn't control would affect one iota the progressive values John Kerry has fought for his whole life,' Seth said in a statement. A Sensenbrenner spokeswoman said in a statement that he 'has never voted for a tax increase in 30 years, and he's not about to start now. And he certainly wouldn't start by supporting a tax increase that would have a negative impact on Wisconsin,' including thousands of employees of the Wisconsin-based GE Healthcare. Sensenbrenner, who reports a net worth of $11 million to $15 million, sees no conflict with his GE holdings because he 'bases his votes on what is in the best interest of his constituents.' 