Unrelated Diversification

Unrelated diversification was the dominant corporate strategy during the conglomerate wave of the 1960s and 1970s, when companies like ITT Corporation, Gulf+Western, and Litton Industries assembled vast portfolios of businesses spanning everything from telecommunications to baking to insurance. The theoretical appeal was compelling: by diversifying across unrelated industries, a company could reduce earnings volatility, allocate capital more efficiently than external markets, and apply superior management techniques across diverse operations. Harold Geneen, CEO of ITT, grew the company from $765 million to $17 billion in revenue by acquiring over 350 companies in industries ranging from hotels to car rentals to food processing.

The academic case against unrelated diversification was articulated most forcefully by Michael Porter in his 1987 Harvard Business Review article 'From Competitive Advantage to Corporate Strategy.' Porter studied 33 large U.S. companies and found that most had divested more acquisitions than they kept, with unrelated diversification performing worst of all. The core problem is what Porter called the 'better off' test: for diversification to create value, the individual businesses must be more valuable together under one corporate umbrella than they would be independently. Unrelated businesses rarely pass this test because the parent company cannot add meaningful operational or strategic synergies.

Despite the academic skepticism, unrelated diversification has succeeded in specific contexts. Berkshire Hathaway, under Warren Buffett, owns businesses ranging from insurance (GEICO) to railroads (BNSF) to confectionery (See's Candies) to batteries (Duracell). Buffett's approach works because Berkshire's advantage is capital allocation: Buffett and his team excel at identifying undervalued businesses, providing patient capital, and allowing autonomous management to operate without corporate interference. In emerging markets, conglomerates like India's Tata Group and South Korea's Samsung have thrived because they substitute for underdeveloped capital markets, talent pools, and institutional infrastructure.

The 'conglomerate discount' is a well-documented phenomenon in which financial markets value diversified conglomerates at less than the sum of their individual business units. This discount reflects investor skepticism that corporate headquarters adds value and the recognition that investors can diversify their own portfolios more cheaply by buying shares in different companies. The result has been decades of corporate refocusing, with companies like General Electric, Siemens, and United Technologies systematically divesting unrelated businesses to focus on core competencies.

The strategic lesson from unrelated diversification is that corporate strategy must articulate a clear theory of value creation. Simply owning multiple businesses is not a strategy. The corporate parent must add value through capital allocation expertise, shared capabilities, or institutional advantages that individual businesses could not access independently. Without this clear value-creation logic, unrelated diversification destroys rather than creates shareholder value.