LONDON -- One of Warren Buffett's famous investing sayings is "Be fearful when others are greedy and greedy only when others are fearful" -- or, in other words, sell when others are buying and buy when they're selling.

But we might expect Foolish investors to know that, and looking at what Fools have been selling recently might well provide us with some ideas for investments that are past their prime. So, in this series of articles, we're going to look at what customers of The Motley Fool ShareDealing Service have been selling in the past week or so and what might have made them decide to do so.

Two-year high (SBRY -1.45%) (JSAI.Y -1.60%)
Shares of Sainsbury have been performing nicely of late, but that may be what put the company in the No. 8 spot in the latest "Top Ten Sells" list (based on aggregate data from The Motley Fool ShareDealing Service). For almost a year, from August 2011 to June 2012, Sainsbury's share price was in something of a trough. But it has risen more than 44% from a low of just less than 260 pence at the end of September 2011, about 20% in the past year, and more than 9% in March 2013 alone, to put the shares on a two-year high.

Sainsbury has managed to avoid the contamination scandal that has nagged at several of its main rivals since news of the presence of horsemeat in beef hit the headlines at the beginning of the year. That might account for why it was the only one of the "big four" supermarkets to increase its market share in the 12 weeks to mid-February, according to research by Kantar Worldpanel. And even without the benefit of escaping a loss of customer confidence in its foodstuffs, Sainsbury had been doing well anyway. In a trading statement published last week, the company reported that total sales for the fourth quarter were up more than 7% and that it had seen "strong growth" in home accessories sales, up nearly 25% year on year, with clothing sales up nearly 20%.

All that good news, combined with the fact that, even after the recent price rise, the shares are expected to yield a dividend of almost 4.5% for 2013 and 4.7% in 2014, ought to make Sainsbury an attractive proposition for income-seeking investors.

But perhaps the share price's substantial growth over the past few months, together with a three-week, 9% rise during which it hit a two-year high, may have been enough to persuade some Sainsbury shareholders -- especially anyone lucky enough to have bought at the end of September 2011 -- to at least take a comfortable profit while the going's good (rather than, as for some of its rivals, only good-to-firm).

A top income share for 2013
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