Sigma-Aldrich (SIAL) is a diversified chemical, life science, and biotechnology company.The company was founded in 1975 and now has a market cap of $16.8 billion.

The company makes the following products:

Sigma-Aldrich is not a normal Dividend Aristocrat stock.Some interesting characteristics of the company that set it apart from other Dividend Aristocrats.

All of the hurdles of the acquisition have been cleared.The acquisition will take place on November 18th, 2015.At this date, Sigma-Aldrich will no longer be a Dividend Aristocrat as it will join Merck KGaA.

While the company is no longer a traditional dividend growth play, it is highly instructive to analyze why Sigma-Aldrich was acquired, and what characteristics other recent Dividend Aristocrats that have been acquired share with Sigma-Aldrich

Dividend Aristocrats Are Being Acquired

There have been 3 Dividend Aristocrats that have been acquired or are pending acquisition since 2014:

These 3 acquisitions mean that over 5% of the Dividend Aristocrats index has been acquired in the last ~2 years.

The first thing that jumps out is the relative size of the acquired companies.Before their acquisitions, these 3 companies had the following market caps:

These companies are all small for a Dividend Aristocrat.

They all maintained strong competitive advantages and had valuable assets that allowed them to grow dividend payments for more than 25 consecutive years in a row.