Why were fed court cases won against monopolies and trust during the gilded age?

So few cases against monopolies and trust, also called The Sherman Act, were won for the fed during the Gilded Age (1870-1900) because it was loosely formulated and failed to define such critical terms as "trust", "combination", "conspiracy" and "monopoly". Despite substantial fees and jail expeditions for those who decided to form such combinations, the Act was dismantled five years later. In other words, monopolies and trusts were encouraged by the federal courts.

Monopolies and trusts were supported by Federal Court so, the Federal courts were supported by monopolies and trusts.