LONDON -- If you want to be eligible for a dividend payment, or if you're watching for possible share price falls, keeping up with ex-dividend dates can prove beneficial: So long as you hold the shares up to and including that day, you'll get your money.

We have a small number of companies from the FTSE 100 and FTSE 250 reaching their crucial dates next week. Here are three that will go ex-dividend next Wednesday, June 5.

Associated British Foods (ABF 2.00%)
On April 23, Associated British Foods declared an interim dividend of 9.35 pence per share for the 24 weeks to March 2. It will be paid on July 5, with an ex-dividend date of June 5. The payment is up 10% on the first-half dividend a year previously, and the firm tells us its profit rise was geared toward the first six months.

Analysts are forecasting a similar rise in the final dividend, which should take the full-year payout to about 31.5 pence per share. That would provide a yield of a modest 1.7% on the current share price of 1,887 pence, but that price is up 60% over the past 12 months.

WPP (WPP 1.21%)
Next Wednesday marks final ex-dividend day for advertising and media giant WPP, and there will be a payment of 19.71 pence per share. Added to an interim dividend of 8.8 pence, that makes a total for the year of 28.51 pence per share. With the shares currently priced at 1,159 pence, it represents a 2.5% yield. That's not a massive yield, but it is about 2.7 times covered -- and shareholders have enjoyed a price rise of about 45% over the year.

Forecasts for the next couple of years look positive too, with a 5% rise in earnings and a 16% rise in the dividend currently being forecast by City analysts. The shares are currently on a forward price-to-earnings ratio of 14.6.

Debenhams (DEB)
We also have ex-dividend day for Debenhams, with an interim payment due of 1 pence per share. That's exactly the same amount the firm paid at the halfway stage in 2012, and if the final dividend remains unchanged as well, then we should see a total of 3.3 pence paid for a yield of 3.6% on the current share price of 92 pence.

The price slumped between October and April, but it has since been recovering and is up about 20% over 12 months. And with the shares on a P/E based on full-year forecasts of less than 10, Debenhams' ongoing share buyback program looks to be well-timed.

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