With declining margins in the industry and left without Citgo's reserves, Mesa and its investor partners kept hunting for a takeover target, only to discover while fighting Gulf for Citgo how increasingly top-heavy its portfolio and declining reserves were undervaluing its overall assets. They subtly but quickly acquired 4.9 percent of Gulf Oil's stock by early fall 1983, just shy of having to declare themselves and their intent at 5 percent to the SEC. In the ten days allowed to prepare the SEC filing, Mesa and its investor partners accelerated buying to 11 percent of the company's stock, larger than the founding Mellon family's share, by October 1983. Gulf responded to Mesa's interest by calling a shareholders' meeting for late November 1983 and subsequently engaged in a proxy war on changing the corporation's by-laws to minimize arbitrage. Pickens made loud criticisms of the existing Gulf management and offered an alternative business plan intended to release shareholder value through a royalty trust that management argued would "slim down" Gulf's market share. Pickens had acquired the reputation of being a corporate raider whose skill lay in making profits out of bidding for companies but without actually acquiring them. During the early 1980s alone, he made failed bids for Cities Service, General American Oil, Gulf, Phillips Petroleum and Unocal. The process of making such bids would promote a frenzy of asset divestiture and debt reduction in the target companies. This is a standard defensive tactic calculated to boost the current share price, although possibly at the expense of long-term strategic advantage. The target shares would rise sharply in price, at which point Pickens would dispose of his interest at a substantial profit.