Actual results may differ materially from such statements due to a variety of factors that could adversely affect the company's operating results. Risks and uncertainties that may affect our results are provided in our press release and in our SEC filings on Form 10-K and Form 10-Q.
Now, let me turn the call over to John Stropki.
Thank you Vince and good morning to everyone. Our results for 2011 fourth quarter were very positive. 2011 sales of $2.7 billion was the highest in Lincoln’s history and also marked the second consecutive year-over-year of very strong sales growth. Sales in 2011 increased 30.2% over 2010, which in their self were up 20% from 2009 results.
We obtained good leverage in most of our business segments. The fourth quarter strong operating results, coupled with continued strength in sales and profitability were particularly encouraging, giving the ongoing uncertainty in economic and political environments in several key markets.
We entered 2012 with very good momentum. Particularly here in North America, our largest segment, where the overall manufacturing environment and relative business metrics continue to improve, especially in the United States. Our strong revenue growth underlines the fact we remain focused, on track and we are executing on our global growth strategy.
Our three U.S. acquisitions of last year are contributing beyond expectations and demonstrating good upside potential. Fourth quarter sales rose 23% to $695 million and net income increased 39% to $57.7 million or $0.68 per diluted share. Full year 2011 net income increased 66.8% to $217 million or $2.56 per diluted share. Vince will provide more detail on the numbers later, but first I’ll review some of the segments and provide a little color about the activity in the regions.
First, North America. In North America, our largest segment, sales were very strong in the quarter, rising 33% year-over-year to $362 million. Third party export sales increased $63 million, up 21% from the fourth quarter of 2010. Exports to the Brit countries improved 37% over the same period. We also announced a price increase in the United States effective October 3, 2011. Machine pricing was increased, an average of about 5%, with certain welding consumables, including select Sub Arc and Flex Cord wires, the pricing increased between 3% to 7%. 2011 North America sales were $1.3 billion, a 29% increase year-over-year.