June 9 (Reuters) -

A lawyer for BlackRock ( BLK ) said on Monday that Republican

states' claim that asset managers violated antitrust law through

industry climate groups was not "plausible," as the firms

pressed to have the case dismissed.

But a lawyer for the states, which include

Texas

and 12 others, told the U.S. District Judge Jeremy Kernodle

that even calling attention to environmental matters, such as by

signing on to industry agreements, could have an impact.

BlackRock ( BLK ), the world's largest asset manager,

Vanguard and State Street are seeking to dismiss the

claims in the closely watched antitrust case. The case, filed

last November, claims the firms violated antitrust law through

climate activism that reduced coal production and boosted energy

prices.

In pressing for dismissal, Gregg Costa, an attorney for

BlackRock ( BLK ), said on Monday that, among other things, the fund

firms never voted against the same coal company directors during

the years in question, weakening the case. Nor did the

plaintiffs bring forward any material such as from a

whistleblower showing direct talks among the companies to

coordinate their activities.

"It's hard to see how this alleged conspiracy is even

possible, let alone plausible," Costa said.

Speaking for the states, Cooper & Kirk attorney Brian

Barnes said the firms' actions could still have a market impact.

"Jawboning by these defendants as to decisions about

market strategy just very clearly has the potential to influence

output decisions at the coal company," Barnes said.

The outcome of the lawsuit could have major implications

for how the companies, which together manage some $27 trillion,

manage their holdings and passive funds.

One possible remedy sought by the plaintiffs would be

for the fund firms to divest holdings in coal companies, which

BlackRock ( BLK ) has said would harm the companies' access to capital

and likely raise energy prices.

Kernodle, of the U.S. District Court for the Eastern

District of Texas, said he would take the matter under

advisement. He also said that like many Americans he owns shares

in various index funds from the firms, including the Vanguard

S&P 500 ETF and the BlackRock ( BLK ) iShares Core S&P Small Cap

fund..

While the ownership would not seem to require his

recusal, Kernodle said parties who disagree should file their

objections within two weeks.