A federal appeals court ruling yesterday guaranteed independent presidential candidate John B. Anderson a place on Maryland's Nov. 4 elecion ballot, thereby clouding President Carter's chances of carrying the state.

In an 11-page opinion, the three-judge panel of the 4th U.S. Circuit Court of Appeals agreed with a lower court judge who said that Maryland filing laws placed an unfair burden on independent presidential candidates. Attorney General Stephen Sachs issued a statement late yesterday afternoon saying he has no plans to appeals the decision.

Yesterday's decision has major implications for the presidential campaign in Maryland, a state where Democrats outnumber Republicians by more than 2-to-1 but where there has been long-simmering discontent with President Carter among traditionally Democratic federal workers and among liberals in the affluent suburbs of Baltimore and Washington.

It is in these ares -- 1montgomery and Baltimore counties in particular -- that Anderson is expected to draw the most votes. And in Maryland, these votes are more likely to hurt Carter than his Republician challenger Ronald Reagan.

"I think it [the decision] will help Ronald Reagan in Maryland," said Republican State party chairman Allen Levey. "People who might have voted for Carter will now be coming out to vote for Anderson in places like Montgomery and Baltimore counties," Levey added.

Carter's deputy Maryland campaign chairman Ed Crawford, however, tended to downplay the effect that Anderson might have on Carter's chances of winning Maryland's 10 electoral votes. "Maryland's been traditionally a heavily Democratic state, and we think that we're communicating the message that we think this is really a two-person race, Reagan and Carter," Crawford said.

However, "it's not an easy task," he conceded. "We're trying to tell people not to be fooled by [Anderson] that white-haired Cheshire Cat. He smiles big, but when you put your hand toward him to try and find substance, he just fades away."

Other politicians from both parties, however, say that Anderson's brand of hard-to-label politics will have great appeal in Maryland. One measure of this potential appeal, they say, is the number of Democratic voters -- 10 percent -- who cast their votes for "None of the above" when faced with a choice between Carter and Sen. Edward M. Kennedy in the May 13 primary which Carter won.

On the Republican side, another 10 percent of the voters cast their ballots for Anderson in the primary -- even though he had declared his independent candidacy several weeks before. "We are defintely elated," with the decision, said Olivia Dorn, press secretary for Anderson's Maryland campaign effort. "We feel like this will really be a big step forward with the campaign. It dispels any fear that supporters might have had" that their efforts would be thwarted by Maryland's election laws.

Yesterday's decision makes Maryland the 34th state in which Anderson has been finally certified for the November ballot, according to Joan Lawson of his national campaign headquarters. He has filed signature petitions and is awaiting certification in 13 other states, and is about to file in New Hampshire, South Carolina and Arizona, she said.

Anderson has already qualified for the ballot in the District of Columbia and is expected to win a ballot spot in Virginia.

In its decision, the federal appeals panel agreed with U.S. District Court Judge Joseph H. Young that the early fitting deadline for independent presidential candidates -- which was part of a law passed in 1978 -- served no legitimate purpose. "Failing to achieve a legitimate purpose, Maryland's earlier filling date . . . is invalid," the judges said in their unanimous, unsigned opinion.

Attorney General Sachs, explaining his decision not to appeal, said yesterday, "There was a Maryland statute that needed a responsible defense. We responsibly defended it. We've now been told by four federal juges that it's unconstitutional . . . We don't want to be a sore loser."

However, in the official statement issued by his office yesterday, Sachs said that he would be watching the outcome of Ohio's effort to persuade the Supreme Court to declare its election laws valid. If such a decision is forthcoming before the fall election, and if it seems relevent to the Maryland case, Sachs said, he might reconsider his decision to abondon further appeals.

The law struck down by the appeals court required an independent presidential candidate to file with state election officials by March 3 -- seven weeks before Anderson dropped out of the battle for the Republicain nomination and declared his independent candidacy.

While pursuing a court battle to overturn the law, Anderson's supporters also gathered nearly 89,000 signatures requesting his inclusion on the ballot. That is 34,000 more than required by state law.