Give readers what they need, and omit what they do not need

Before

Outstanding Old Co. Stock Options: Pre-August 2009 Old Co. options were fully vested and exercisable and converted into options to acquire Buyer common stock upon completion of the acquisition on February 5, 2010. They remain exercisable in accordance with their terms.

In addition, upon completion of the Old Co. acquisition, options granted in August 2009 (August 2009 Options) were converted into options to acquire Buyer common stock. The August 2009 Options will continue to vest 1/5 per year commencing with the first anniversary of the date of grant. If Mr. Smith’s employment had been terminated by Buyer without cause or by Mr. Smith for good reason or due to death or disability, all outstanding August 2009 Options would have immediately vested and been exercisable. Per the vesting schedule, 1/5 of his August 2009 Options vested on August 20, 2010, August 20, 2011, August 20, 2012, and August 20, 2013.

Before, with commentary

Outstanding Old Co. Stock Options: Pre-August 2009 Old Co. options were fully vested and exercisable and converted into options to acquire Buyer common stock upon completion of the acquisition [this assumes the reader knows about the acquisition] on February 5, 2010 [the reader does not need this date]. They remain exercisable in accordance with their terms.

In addition, upon completion of the Old Co. acquisition, options granted in August 2009 (August 2009 Options) [If you can make your meaning clear without using a defined term or a lot of extraneous words, you should.] were converted into options to acquire Buyer common stock. The August 2009 Options will continue to vest 1/5 [“20%” or “one-fifth” seems more professional] per year commencing with the first anniversary of the date of grant. If Mr. Smith’s employment had been terminated by Buyer without cause or by Mr. Smith for good reason or due to death or disability, all outstanding August 2009 Options would have immediately vested and been exercisable. Per the vesting schedule, 1/5 of his August 2009 Options vested on August 20, 2010, August 20, 2011, August 20, 2012, and August 20, 2013. [This is completely unnecessary since the company already said options would vest 1/5 per year on the anniversary of the grant. Even those of us who aren’t math oriented can handle this!]

After

Outstanding Old Co. Stock Options: At the time of Buyer’s acquisition of Old Co., Mr. Smith held fully vested and exercisable options to acquire Old Co. common stock. When the acquisition was completed, those options were converted into options to acquire Buyer common stock. They remain exercisable in accordance with their terms.

In addition, upon completion of the Old Co. acquisition, certain of Mr. Smith’s options to acquire Old Co. stock that were not fully vested were converted into options to acquire Buyer common stock. These options continue to vest 20% per year, on the anniversary of the August 20, 2009, grant date. If Mr. Smith’s employment had been terminated by Buyer without cause or by Mr. Smith for good reason or due to death or disability, all of the converted options would have immediately vested and been exercisable.