If bought at a reasonable price and well administrated, catalogues are considered an excellent investment. They are such good investments, in fact, that it is increasingly difficult to find one on the market. The rule among today's songwriters after the Beatles' example: Never sell your publishing.

Explained Marshall Gelfand, Jackson's accountant and business manager: "You've got to remember that when the Beatles started nobody in this business owned their own publishing. It wasn't until the mid-'60s, when artists like Dylan and the Beatles started recording their own songs and selling millions of albums, that advisers began to understand the importance of holding onto your own publishing.

"The key thing to remember today is don't sell your catalogue. The whole explosion of music videos and the trend toward using more music in movies is going to make copyrights even more valuable. If you are an established artist today, you should only consider selling your catalogue as a last resort to raise cash."

So, why didn't McCartney buy back the rights?

McCartney reportedly made offers to ATV over the years but--according to those close to the Jackson/ATV negotiations--he wasn't a serious bidder in recent years. Among the competition for ATV's rights: Charles Koppelman and Marty Bandier's New York-based the Entertainment Co., London-based Virgin Records, New York real estate tycoon Samuel J. Lefrak and financier Charles Knapp.

A spokesman for McCartney said the ex-Beatle had no comment on the ATV acquisition, but an ATV representative--who asked not to be identified--speculated that McCartney wanted his own songs, but perhaps wasn't willing to pay for thousands of other copyrights in the ATV catalogue. (The Beatles' portion of the collection alone was estimated by one source to be worth about two-thirds of the purchase price.)

But McCartney was involved in an amusing sidelight: "Holmes a Court's people were convinced for a while that Michael was a shill for Paul," said a party to the negotiations.

"It seems Paul's people once told one of the ATV officers that their client was interested in buying the copyrights, but that he didn't want to go through lengthy negotiations. They said, in effect, 'You go out and get your best offer and we'll pay 10% more.'

"So, when Michael shows up, they know he is a friend of Paul's and they suspect his bid is just a way for Paul to avoid paying the extra 10%. It took a long time to convince them that Michael was acting on his own."

Jackson set out strictly to buy copyrights. But the package included buildings, a recording studio and some studio equipment--and a life insurance policy on his friend, McCartney McCartney.

Northern Songs had taken out insurance policies on all four of its principal owners, a common business practice. That means there was also a policy on John Lennon. Presumably, ATV collected on that in 1980.

Many pop fans may have been surprised when Jackson demonstrated the ambition and resources to pull off such a complex business deal. But the people close to the pop star were not surprised.

Frank Dileo, his personal manager, said he has long been impressed by Jackson's "sound business sense. A lot of artists don't want to know anything about business affairs, but Michael is involved in every facet of his career. He's not one of those people who stops thinking when he walks out of the recording studio or off the stage."

Jackson was just beginning to build his own team of advisers six years ago when he hired Branca. Until then, Jackson's father, Joseph, had guided the affairs of all six brothers.

In Branca, Jackson found someone who was young (Branca's now 34), easy to relate to and tough-minded. A native of Bronxville, N.Y., Branca was a law review editor at the UCLA Law School and represented such clients as the Howard Hughes heirs and the UCLA Foundation before joining the firm of Ziffren, Brittenham and Gullen in 1981.

By the time the "Thriller" album was released in late 1983, Branca had been out to Jackson's house in Encino for so many meetings that he barely had to think about his driving.

He could concentrate on business matters as he departed from his office in Century City, drove west on Olympic Boulevard, then north on the San Diego Freeway, west on the Ventura Freeway, then the Hayvenhurst Avenue off-ramp.

The issue on his mind that afternoon in 1983 was copyrights. "Thriller" already was racing up the charts, showing every sign of becoming a blockbuster (it is now nearing the 40-million mark worldwide). That success meant CBS would have to renegotiate Jackson's contract.

As in pro baseball, contracts are frequently torn up in the record business when an artist moves dramatically to a higher level of success. Double your home-run output to 50 and you get a new contract, even if you are bound by a 10-year agreement. Double your record sales to 10 million and it's the same thing.

There is no legal obligation to sign a new contract, but companies want to keep their artists happy. As sales increase sharply, companies stand to make more money even if they pay a higher royalty.