Complex sentence: LinkedIn filed for an initial public offering in January 2011 and traded its first shares on May 19,2011, under the NYSE symbol "LNKD", price of IPO was $45 per share.
Split into simpler sentences: LinkedIn filed for an initial public offering in January 2011. The company traded its first shares on May 19,2011, under the NYSE symbol "LNKD", at $45 per share.