In 1930, Sidney Weinberg assumed the role of senior partner and shifted Goldman's focus away from trading and towards investment banking. It was Weinberg's actions that helped to restore some of Goldman's tarnished reputation. On the back of Weinberg, Goldman was lead advisor on the Ford Motor Company's IPO in 1956, which at the time was a major coup on Wall Street. Under Weinberg's reign the firm also started an investment research division and a municipal bond department. It also was at this time that the firm became an early innovator in risk arbitrage.
Gus Levy joined the firm in the 1950s as a securities trader, which started a trend at Goldman where there would be two powers generally vying for supremacy, one from investment banking and one from securities trading. For most of the 1950s and 1960s, this would be Weinberg and Levy. Levy was a pioneer in block trading and the firm established this trend under his guidance. Due to Weinberg's heavy influence at the firm, it formed an investment banking division in 1956 in an attempt to spread around influence and not focus it all on Weinberg.
In 1969, Levy took over as Senior Partner from Weinberg, and built Goldman's trading franchise once again. It is Levy who is credited with Goldman's famous philosophy of being "long-term greedy", which implied that as long as money is made over the long term, trading losses in the short term were not to be worried about. At the same time, partners reinvested almost all of their earnings in the firm, so the focus was always on the future. That same year, Weinberg retired from the firm.
Another financial crisis for the firm occurred in 1970, when the Penn Central Transportation Company went bankrupt with over $80 million in commercial paper outstanding, most of it issued by Goldman Sachs. The bankruptcy was large, and the resulting lawsuits, notably by the SEC, threatened the partnership capital, life and reputation of the firm. It was this bankruptcy that resulted in credit ratings being created for every issuer of commercial paper today by several credit rating services.
During the 1970s, the firm also expanded in several ways. Under the direction of Senior Partner Stanley R. Miller, it opened its first international office in London in 1970, and created a private wealth division along with a fixed income division in 1972. It also pioneered the "white knight" strategy in 1974 during its attempts to defend Electric Storage Battery against a hostile takeover bid from International Nickel and Goldman's rival Morgan Stanley. This action would boost the firm's reputation as an investment advisor because it pledged to no longer participate in hostile takeovers.
John L. Weinberg (the son of Sidney Weinberg), and John C. Whitehead assumed roles of co-senior partners in 1976, once again emphasizing the co-leadership at the firm. One of their initiatives was the establishment of 14 business principles that the firm still claims to apply.