[CORRECTION: A correction had been added to this story]

Sixty percent of the tax credits went to six highly profitable companies. Shire HGT Inc. of Lexington received the top amount — $5.9 million – just as it did in last year’s inaugural round of tax credit awards by the Massachusetts Life Sciences Center.

The other top recipients were Sanofi-aventis US Inc. of Cambridge ($2.45 million), Vertex Pharmaceuticals of Cambridge ($2,424,173), NX Stage Medical Inc. of Lawrence and Merrimack Pharmaceuticals of Cambridge (both $1.3 million), and Novartis Institutes of Cambridge ($1.1 million).

Most of the awards this year went to first-time winners, but there were a handful of repeat customers. In addition to Shire, Merrimack Pharmaceuticals, Lightlab Imaging Inc. of Westford, Nova Biomedical Corp. of Waltham, Organogenesis Inc. of Canton, and Still Rivers Systems of Littleton all received awards for the second year in a row. (To read the press release, click here.)

Geographically, Cambridge was the big winner. Ten companies in Cambridge received a total of $9.6 million, or 40 percent of the total.

The tax credit program was created in 2008 when the Legislature passed a $1 billion life sciences law that authorized the state center to issue up to $25 million in refundable tax credits a year for 10 years. Refundable credits are an unusual breed of tax credit. They can be used to reduce dollar-for-dollar a company’s tax bill or they can be converted to cash by selling them to the state or a third party. [Due to a reporting error, the life sciences tax credit was mischaracterized. It can be sold to the state but not to a third party. Transferable tax credits can be sold to third parties.]

The application process for the life science tax credits lasts much of the year. Credits are steered to companies that pledge to create jobs in the coming year. Recipients vary in size, from startups to industry behemoths. Sanofi-aventis, which received tax credits worth $2.45 million, is a French company with a market value of $85 billion that is currently trying to buy Genzyme Corp. of Cambridge for $18.5 billion.

Other big companies receiving tax credits include Novartis ($135 billion market value), Shire ($8.6 billion market value), Vertex ($7.2 billion), Ironwood Pharmaceuticals of Cambridge ($1 billion), and Caliper Life Sciences Inc. of Hopkinton ($322 million).

Organogenesis is a darling of the Life Sciences Center. It received tax credits worth $245,000 last year and a grant worth $7.4 million. It received tax credits worth $457,899 this year.

Officials say companies that fail to live up to their job commitments will be subject to so-called claw-back provisions, effectively the withdrawal of the tax credits. A spokesman for the Life Sciences Center said companies have a full year to meet their job targets and claw backs would not begin until a year later.