edited 4-4-2016
1.  Sustainable Competitive advantage defending or growing market share in its specific market.  This is the sine qua non of our investment choices and the foundation of our approach to investment.  The company with a competitive advantage is rare.  It is marked by the ability to increasingly attain returns on investment above its cost of capital, and above those of its competitors.  A competitive advantage might be made durable by low cost/high volume leadership among competitors; barrier to market entry of competitors; product differentiation/switching costs to customers.  The company with a sustainable competitive advantage sells an indispensable product.

2. No competitive advantage truly lasts for ever. Hence, a related critical facet of the competitive advantage feature is that management consistently anticipates or reacts to changes in the market or competitive landscape by finding profitable ways of extending the company’s competitive advantage into new markets that are tangibly related to its current markets. That is, the company adapts and evolves to perpetuate its competitive advantage by extending it into the evolving new markets.

3.  Evidence of devotion to shareholders by its capital allocation, manifested in the following ways
stock buybacks to reduce share count
avoiding excessive dilutive stock compensation
obtaining good returns on investments in acquisitions
aligning reward and performance of management and employees to reward shareholders and long term company performance
allowing shareholders to have voting power commensurate with their stock ownership.

4  Common stock of publically traded company based in U.S. or other relatively transparent legal environment with respect for property rights, at least 10 years old.

5. The investment worthy activities of the business are demonstrated in the record of its past and present achievements, not in the hoped for future.

6.  quantitative evidence of ability to obtain returns on investment above cost of capital, such as low debt level, growing free cash flow, high free cash/revenue, high gross margin, high ROE and ROI.