John Wood's family have been selling their stake in the company that bears his name, and that has sent a shiver through the share price. Some £130m worth of shares were sold by certain family members and trusts at the end of last month, although Sir Ian Wood, the founder of the company that split off from what was Scotland's largest fishing company in the 1980s, was not among them.
Some analysts sniffed a buying opportunity from the shares' wobble. Were they right? Today Wood Group issued a pre-close trading update that said its results would be in line with expectations. It said it expects to grow further in 2013, on the back of favourable market conditions.
In other words, oil companies around the world are still willing to spend capital on big projects, and companies such as Wood Group shouldn't be short of work, although it will be at least another year before its problematic contract in Oman starts making money.
So why are the family selling up? Perhaps some of them need cash. Perhaps they want to spread their money around a broader a group of companies. There can be any number of reasons. It's not necessarily a red flag for other investors although it should be taken into account.
I last looked at oil services in March when I said Wood Group was one of the tougher members of the sector to make a judgement on. I came down in favour of taking profits. The shares were then at 719p. They're a little higher now, but I'm not losing any sleep over it. It's not the worst call I've ever made.
On valuation grounds, at 14.4 times earnings with a prospective yield of about 1.4 per cent, John Wood doesn't look all that attractive. I don't especially see the buying opportunity some of the analysts do in the wake of the family sell-off, so I'd steer clear for now – particularly as there are better opportunities in the sector.
It is also worth noting that if you are considering investing in Wood Group or its peers, many are involved in work that some people might find controversial – oil sands being one example. So if you prefer your portfolio to have a green tinge, that's another reason for steering clear.
Looking just at the financials, Amec would remain my top tip. The most recent newsflow came at the beginning of the month when the business announced the award of a $528m (£330m) project management consultancy contract by the Kuwait National Petroleum Company for a new oil refinery at Al Zour. When completed, it will be the biggest in the Middle East, and will create 300 jobs at the company.
That came two weeks after a fairly upbeat trading statement, which suggested that business remains buoyant. Amec's shares haven't been flying recently. Wood's have outperformed them in the second half (although Amec has been gaining ground recently).
All the same, the group was one of The Independent's ten to follow at the start of the year. Today, Amec is comfortably ahead of its 2011 close of 907.5p although it is a little off the 1136p at which I said keep buying when I last looked at the sector.
Charles Stanley, the broker, recently highlighted the fact that Amec is planning to gear up (borrow more) because it feels its customers no longer need the reassurance of cash on the balance sheet before contracting with it.
That always makes me slightly nervous, however healthy a business is. But there may be a special dividend (good) or a share buyback (less good although it should support the share price).
Amec already offers a decent (3.2 per cent) prospective yield for the sector, and the valuation of 13.7 times full-year forecast earnings doesn't looked stretched yet. I would still rate the stock as a buy because you might as well take advantage if it starts throwing cash at shareholders.
Petrofac I viewed as worth buying if the shares, at 1656p, showed any signs of weakness, which they did in the summer, hitting a low of 1357p in June. They are now at 1706p and trade on 14.7 time earnings, with a forecast yield of 2.3 per cent.
Generally, prospects for oil services firms look quite good, and Petrofac has been a long-term winner. But here is the red light. As I revealed in May, deep within last year's annual report was the fact that the company last year paid $1.4m (£900,000) to hire a corporate jet from an offshore trust linked to the chief executive and founder.
The company's PR people got all hot under the collar, and said the directors of Petrofac used a chartered aircraft for "business travel to ensure they can work effectively across the business for journeys that would be impracticable using standard commercial flights".
It is true that Petrofac has businesses in far-flung places, but the arrangement is bad practice.
There a case for taking profits if you bought in the summer. I would rate the shares as a hold although you should use your vote at the annual general meeting to register your disapproval if the 2012 report reveals the plane arrangement in still flying.
Finally to Hunting Group. I said buy at 925p, but out of all the shares in the sector, it has been a big disappointment. It didn't help that the chief executive dumped 100,000 shares at 945p in May. On 14 times full-year earnings, yielding 2 per cent, it is just about worth sticking with the company. Hold.