band's biggest hits, such as "Ring Ring" (1973), "Waterloo" (1974), "Honey, Honey" (1974), "I Do, I Do, I Do, I Do, I Do" (1975), "Mamma Mia" (1975), "S.O.S" (1975), "Dancing Queen" (1976), "Knowing Me, Knowing You" (1977) and "The Name of the Game" (1977). Sometimes referred to as the "fifth member" of ABBA, Anderson also owned the band's record label and publishing company. He shared the ownership with Benny Andersson, Björn Ulvaeus and Michael B. Tretow, the main sound engineer for the company. Anderson was one of the dominant figures behind ABBA, representing their commercial interests and global success through successful record deals. At the same time, he also managed the investment of funds and the enormous financial incomes of Polar Music, holding the majority of stocks. This was an agreement dating back to 1974, and a great deal of the money came from individual record deals he struck for the group, including a ground-breaking agreement for record sales in the Soviet Union in which ABBA recordings were released in exchange for barrels of oil. In the mid-1980s, a considerable part of ABBA's fortune was lost by mismanagement, bad investments, high demands for tax and the rise of credit rates. Legal disputes The contract with the performers, as well as the international distribution, ran from a standard publishing and recording deal involving identical contracts, rather than from one written specifically with the performers of the band. This led to problems later, when three of the four ABBA members terminated their relationship with Anderson when it was revealed that Anderson had used this contract to take a percentage of profits at a value of 4.5 million euros over the course of many years. A complaint against Anderson was submitted to the Stockholm District Court in June 1990 by Agnetha Fältskog's company Agnetha Fältskog Produktion AB, Benny Andersson's company Mono Music AB, as well as a Dutch company holding Björn Ulvaeus's rights. The dispute was eventually settled out of court in July 1991; the terms of the settlement remain undisclosed. In 1982, Anni-Frid Lyngstad had sold all the shares in the Polar Music company given to her by Anderson, as she moved abroad. She remains the only member of the band never to seek legal recourse for past royalty fees and was not involved with the legal proceedings against Anderson. Polar Music Prize In 1989, Anderson made a substantial financial endowment to