CHICAGO, Ill. — The impact of the federal Dodd-Frank Act passed in the wake of the mortgage and investment banking crisis of 2008 is now being felt in the nation’s commodity exchanges.

With the collapse of once-iconic investment houses Bear Stearns and Lehman Brothers to speculative trading, government regulators have put rules in place that would require speculators to pay more in order to make trades. The regulations being crafted by the Commodity Futures Trading Commission (CFTC), which regulates the futures markets, essentially would treat all traders – even those involved in hedging – as speculators.

A rule that increasing the amount of money traders would have to set aside in margin accounts went into effect May 7, but the CME Group, the nation’s largest exchange, sought and received a 90-day extension. Beside agricultural commodities, the CME trades in precious metals, currency, oil and other futures on Chicago and New York exchanges.

The CME told the CFTC the additional margin requirements could cause serious disruptions in its corn and oil markets.

The CME said it will work with the CFTC and other government regulators to make the transition for its members as smooth as possible before the rule goes into effect at its exchanges on Aug. 5.

Steve Erdman, president of EFG Group, a commodity futures trading firm in Chicago, said there are some who think the new rule will be bad for the markets by decreasing liquidity.

“There are a lot of regulators who think what really needs to happen is more transparency. For example, if there was more transparency in the markets, no one would have been surprised this week when J.P. Morgan announced at a press conference it had lost $2 billion in hedging contracts,” said Erdman.

“What we need is more liquidity, not less. Small investors need more liquidity because they have a calming effect on the big traders, who have been reduced to static, electronic trades.”

A margin call works like this: If a trader buys $100,000 in commodities but only has half that amount to make the purchase, he can borrow the rest from a broker. But if the market value of that commodity drops, so does the equity in the trader’s account.

Taking into consideration the maintenance fees the brokerage charges, a trader can end up holding a security worth less than what they paid for it; think of it as an upside-down mortgage. The brokerage will ask the trader to put more money into the account in order make up the difference. If the trader doesn’t have the money, the broker will issue a margin call and then can sell the trader’s assets to make up the difference.

Erdman said the idea behind the change is to raise confidence in the markets by forcing traders to put up more money for their trades. While that sounds good in theory, he said commodity traders have been jumpy over that issue in the wake of the collapse of M.F. Global.

The once-respected company filed for bankruptcy on Oct. 31, 2011, and is under investigation for misappropriating more than $1.6 billion in investor funds. Many of those were agricultural investors who had put up money to back their trades – the very thing the CFTC is mandating.

“I think that is behind everyone’s feelings on this issue,” said Erdman. “Everyone is trying to keep up with what’s going on in the markets today, and it’s difficult to do.”

He said another big change for CME is its switch from a member-owned exchange to a stockholder-owned exchange. The switch was made years ago, but the culture hasn’t changed as fast.

“Overnight, the motivation for the CME changed from making money for its members to making money for shareholders. They’re not as interested in making money for members anymore,” Erdman said.

That’s why this rule change is causing concern among members, who feel they’re being used to prop up shareholder profits, he added. In the end, Erdman said he doesn’t see the margin change rule having that much of an impact on large corporate traders.

“It won’t impact the big boys at all. They’re trying to make the market less volatile with the rules change, but all it’s going to do is take liquidity out of the market.”

And when liquidity disappears, Erdman said small traders, the ones who need the cash to make their trades, won’t be able to make as many trades as they used to because they won’t have the liquidity.