Rep. Chris Collins is claiming innocence as he faces insider trader charges over his involvement in the biotech company Innate Immunotherapeutics Limited. Federal prosecutors allege Collins gave his son inside information about the results of a clinical trial, allowing him to sell shares in the company before values sunk.

New York's Collins — who says he's still running for reelection in November — is the only member of Congress charged with a crime in the indictment. But at least five other Republican members of Congress also purchased shares in the Australian biotech company at some point. They include Rep. Mike Conaway, R-Texas; Rep. Markwayne Mullin, R-Okla.; Rep. John Culberson, R-Texas; Rep. Billy Long, R-Missouri; and Rep. Doug Lamborn, R-Colorado. Another former congressmen, Tom Price, who became Health and Human Services secretary but left office over scrutiny of his travel habits, also held and sold stock in Innate at one point. None of the others are known to be under investigation and some still own the stock.

Collins serves on the board of directors of Innate, an Australian company whose primary business was the development of a single drug intended to fight multiple sclerosis. Clinical trials found the drug was ineffective, as the chief executive officer of the company told Collins and other members of the board in an email on June 22, 2017, according to the indictment. Prosecutors allege that Collins called his son from the White House congressional picnic on June 22, 2017 as soon as he read the CEO's email and urged him to sell his stock before it plummeted.

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Many of the members who held or hold stock purchased it in January 2017, when it was at its zenith. There was some news coverage of the company at the time, including a Jan. 13 article in the New York Times about Price's and Collins' involvement with the company.

The value of the shares dipped in February, before falling by 92 percent in June, after news of a failed mid-stage clinical trial broke.

Former Rep. Tom Price, R-Georgia

Price, according to a financial disclosure form filed with the Office of Government Ethics, sold between $250,000 and $500,000 worth of stock in Innate in February 2017. The Wall Street Journal reported that Price sold his Innate shares that month for $320,000, more than tripling his initial $94,000 investment.

February 2017 was the month Price was sworn in as HHS secretary, and had to sell much of his stock to comply with ethics rules. Price is now a private citizen, after he resigned from HHS amid intense scrutiny over his frequent use of private charter planes.

Markwayne Mullin, R-Oklahoma

Mullin purchased 110 shares of stock in Innate worth between $100,0001 and $250,000 on January 12, 2017, according to his most recent financial disclosure form. He still owns the stock.

A spokeswoman for Mullin said he learned about Innate when its drug became newsworthy, and while Price, who owned shares in the company, was under consideration to be HHS secretary. She pointed out that he isn't under investigation. Mullin is a member of the House Energy and Commerce Committee's Subcommittee on Health.

"Congressman Mullin learned of Innate when it became a newsworthy topic," his spokeswoman, Amy Lawrence, said. "When then-Congressman Tom Price was being considered as the secretary of Health and Human Services, the Congressman decided to invest in Innate, only after doing his own personal research of the company. He still owns the stock and he is not under investigation."

Mike Conaway, R-Texas

Conaway purchased between $1,001 and $15,000 in Innate stock on Feb. 3, 2017, according to a financial disclosure form filed with the House clerk.

His spokesperson noted Conaway has a friend who suffers from multiple sclerosis and thought Innate's drug showed promise.

"Mr. Conaway initially invested in Innate Immunotheraputics because it was a promising breakthrough to treat multiple sclerosis (MS), which impacts a close friend of his," Emily Hytha, spokeswoman for Conaway, said "Strict ethics laws and reporting requirements regulate investments made by members of Congress, which Mr. Conaway follows without exception."

John Culberson, R-Texas

Culberson sold between $1,0001 and $15,000 in Innate stock on June 12, 2017, according to a financial disclosure form filed with the House clerk. That was 10 days before Collins allegedly called his son and told him to sell his stock ahead of the plummet.

Billy Long, R-Missouri

On January 25, 2017, Long purchased between $15,001 and $50,000 in Innate stock, according to his financial disclosure form filed with the House clerk.

Long, like Mullin, is a member of the House Energy and Commerce Committee's Subcommittee on Health.

Hannah Smith, press secretary for Long, said, "Congressman Long did not learn of Innate Immunotherapeutics through a colleague, but rather when it became a daily topic on the nightly news in January of 2017."

Doug Lamborn, R-Colorado

Lamborn purchased between $15,001 and $50,000 in Innate stock on January 24, 2017, according to a form filed with the House clerk. Then on June 27, 2017, he sold what he described as less than $1,000 in stock in the company, after the stock tanked.

Savannah Frasier, spokeswoman for Lamborn, said, "Congressman Lamborn has said previously he invested in the stocks based on his own independent research. Since this was first reported about a year and a half ago, Congressman Lamborn has stood by that. Thus, nothing about Rep. Collins' indictment today would change his statement."

— CBS News' Rebecca Kaplan contributed to this report.