The top five largest Canadian software companies, by market capitalization, are Constellation Software Inc. (TSX: CSU.TO), OpenText Corporation (Nasdaq: OTEX), Mitel Networks Corporation (Nasdaq: MITL), Points International Ltd. (Nasdaq: PCOM) and Enghouse Systems Ltd. (TSX: ESL.TO). Canada is a leading country in software development. Canadian software firms account for nearly one-third of the 250 largest companies in Canada.

Constellation Software, Inc.

Constellation Software, Inc. has a market capitalization of $11.67 billion and annual revenues of over $1.6 billion. It operates internationally, offering its market-leading software and services to a number of industries that function in both public and private sectors.

Constellation Software was established in 1995. The goal was to amass a portfolio of growing market software companies that possessed the qualities necessary to make them leaders in their particular markets. Through a combination of acquisitions and organic growth, the company has experienced rapid growth and established an arrangement of companies that service a large and diverse customer base. Constellation provides its services to over 30,000 consumers, operating in more than 30 countries worldwide. The company has offices throughout North America, Australia and Europe, and it employs more than 9,000 workers.

OpenText Corporation

OpenText Corporation, with a market cap of $5.61 billion and annual revenues of approximately $1.7 billion, remains one of the top Canadian software companies. Headquartered in Ontario, the company cultivates and sells enterprise information management, or EIM, software solutions to major companies in a large variety of industries. Such software is designed to make optimal use of information within a company to enable company management to operate the business with the greatest efficiency. OpenText software applications are utilized to manage content or unstructured data for many types of governance and monetization requirements for large companies, professional service firms and government agencies.

OpenText’s ongoing growth is due in large part to its many acquisitions. It has acquired a number of major companies, including the Actuate Corporation, the Information Graphics Corporation, GXS Inc. and Cordys. OpenText is a publicly traded company, listed on both the Nasdaq and the Toronto Stock Exchange. The firm employs approximately 8,700 people.

Mitel Networks

Mitel Networks provides unified communications solutions to a variety of businesses. It has a market cap of just under $1.7 billion and annual revenues in excess of $900 million. A change in ownership in 2001 led the company away from producing TDM PBX systems and shifted focus almost entirely to Voice-over-Internet Protocol, or VoIP products.

Headquartered in Ontario, Mitel has partners, offices and resellers around the world. It became a public company in 2010, with an initial public offering, or IPO, at $14 per share. In 2013, Mitel announced its acquisition of key supplier, prairieFyre Software Inc., for a net cash cost of approximately $20 million. Mitel went on to make another large acquisition later in the same year, purchasing Aastra Technologies. In 2015, it announced plans to purchase Mavenir Systems for over $550 million.

Points International, Ltd.

Points International offers a sphere of technology and e-commerce services to loyalty program operators. It has a market cap of $1.52 billion and annual revenues over $260 million. It owns and operates, the world’s number one reward program website. The site is a portal where consumers are able to buy, share, swap, gift, and redeem miles or points through loyalty programs offered by a variety of retail partners.

Points International has either client or operating relationships with all the largest loyalty programs in the world. Programs that participate with Points International include American Airlines AAdvantage program, Wyndham Rewards, Delta SkyMiles and British Airways Executive Club.

Enghouse Systems, Ltd.

Enghouse Systems, Ltd. develops and sells enterprise software solutions internationally, operating through three divisions: Enghouse Networks, Enghouse Transportation and Enghouse Interactive. Among Enghouse’s customer base are financial services companies, hospitality firms, health care corporations and public utilities. The firm's market cap is approximately $1.36 billion, and the company generates annual revenues of nearly $300 million.

Founded in 1984, Enghouse maintains its headquarters in Markham, Canada. Internationally, it has operations in the United States, the United Kingdom, throughout western Europe and in Israel, Singapore, Hong Kong and Australia.