LONDON -- The FTSE 100 (INDEX: ^FTSE) index recently broke through the 6,000 point mark for the first time since 2011. Friday's close of 6,122 represents a good gain from the 5,600 level seen in mid-November and is 16% above last year's summer low of 5,260.

The price-to-earnings ratio of the index currently stands at 12 and the dividend yield at 3.6%. Back in June, the P/E was just 9.4, and the yield was 4%. So the Footsie is today rated significantly higher than it was six or seven months ago.

Let's discuss some of the directors who have taken advantage of this highflying market to bank profits by selling shares in their own companies.

Diageo (DGE -1.88%) (DEO -1.48%)
Paul Walsh, CEO of drinks giant Diageo, is one of the longest-serving FTSE 100 chief executives. He took up his post in 2000, having previously been the group's chief operating officer.

Walsh has disposed of a net 73,051 Diageo shares since the start of November, mainly in two big sales: 50,000 shares at 1,801 pence and 20,000 at 1,850 pence, bagging him more than 1.25 million pounds. Walsh's best sell price was at 19.4 times Diageo's earnings; this time last year, the P/E ratio was 16.7.

Walsh's share sales may not have been quite at Diageo's recent high, but the price has drifted down of late, and the shares currently trade at 1,789 pence. Nevertheless, despite the disposal, the chief executive retains a substantial holding of more than 700,000 shares.

Any further sales by Walsh could fuel rumors -- which have been circulating for a while -- that he intends to step down from the drinks group. One rumor has it he will take up the chairman's role at Unilever, where he's already a nonexecutive director.

TUI Travel (LSE: TT)
Tour operator TUI Travel has fared relatively well in the past few recessionary years compared with many of its rivals. The shares soared last year with improved trading, and the travel group was promoted from the mid-cap index to the FTSE 100 in December.

On Dec. 4, the day after TUI announced its annual results, all the executive directors made big share sales at just more than 277 pence. CEO Peter Long sold 748,729 shares, deputy CEO Johan Lundgren sold 350,000, and CFO William Waggott sold 120,000. These were substantial sales -- the chief executive alone netted over 2 million pounds -- even though, a couple of days later, TUI announced chunky awards for the executives under an annual bonus scheme, which bumped their interest in the company's shares back up again.

TUI's shares have continued to rise and are currently trading at 283 pence. That gives a P/E of 11 and a dividend yield of just more than 4%, both of which are better "value" than the market average.

Investec (INVP -0.20%)
International banking and financial-services group Investec is a 2.7 billion pound FTSE 250 firm. Like those of the big blue-chip banks, Investec's shares have been on a tear in recent months.

On Dec. 18, chief executive Stephen Koseff sold 250,000 shares at about 408 pence, pocketing more than 1 million pounds. He continues to hold more than 4.5 million shares, though, which is perhaps just as well, as the price has continued to soar.

Investec's shares are currently changing hands at 448 pence. Analysts' earnings estimates for the year to March 2013 give a P/E of around 12, falling to less than 10 next year, as a result of forecast double-digit earnings growth. The forecast dividend yield rises from 3.8% to 4.6% on the same timescale.

Cairn Energy (CNE -0.24%)
Cash-rich oil explorer Cairn Energy, a 1.7 billion pound mid-cap firm, has only joined in the Footsie rally since the start of January. The shares are currently trading at 283 pence, making hefty sales connected with Cairn's founder and now chairman, Sir Bill Gammell, look rather ill-timed.

The sales on Dec. 12 were made at 263 pence -- close to the shares' six-month low. Lady Janice Gammell, the chairman's wife sold 551,909 shares for 1.5 million pounds, and two trusts in which Sir Bill has a beneficial interest sold 260,000 pounds' worth of shares.

The sales more than halved the Gammell family's stake in the company that's hoping to hit the same kind of jackpot with its exploration in Greenland that it enjoyed in India a few years ago.

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