Motorola Solutions' stock has risen almost 30% since the split and is now about 11% ahead of our $45 price estimate (before the Icahn buyback). Icahn will receive a price of $49.15 per share, a premium of around 10% over our fair estimate for the company's business. We believe Icahn is cashing out at the right time as the markets have bid up the stock ahead of our intrinsic value estimates. The stock has risen almost 14% since its latest earnings call.

Given the low-risk nature of the company's business as it deals primarily in critical sectors such as public safety and emergency services, we believe the company will perform well in the future but the market upside to its current price is minimal.

Icahn is also looking at a huge windfall from his Motorola Mobility investment. Google (GOOG) will be acquiring Motorola Mobility this year after it secures all the regulatory approvals for $40 a share, a huge 63% premium to its market cap on the day the deal was announced in August. We have a fair price estimate of $22 for Motorola Mobility's business. The acquisition has already received the approval of regulatory bodies in Europe and the U.S., though Taiwan and Israel have yet to sign off on the deal.

Both the Motorola split and the Google acquisition were the handiwork of Icahn, who will be extremely pleased with the value he has created. He had argued strongly that Motorola should look to increase shareholder value by splitting the business first and then maximizing the value of its strong patent portfolio. With these moves, Icahn's activism has not only helped himself, but also other Motorola investors.