In an oil sector already excited by the increase in the crude price, Lasmo shares put on an intriguing performance.
The bidder, Enterprise Oil, helped along by bullish comments from securities house Credit Lyonnais Laing, was also strong.
But many observers believe Lasmo's sudden display of strength had only a remote link with the Enterprise advance. A sudden surge of buying, partly for the new account, sent the shares 8p higher to 149p.
Enterprise improved 16.5p to 414.5p. This week, Enterprise increased its offer.
Its failure to put any cash on the table and its far from generous paper terms left many with the impression it had little confidence in its own bid strategy.
From the start of hostilities, when it appeared that the upsurge in Lasmo shares forced Enterprise into a reluctant admission it was looking at its oil rival, its conduct has seemed to lack conviction.
With Lasmo still below the Enterprise bid terms and looking likely to retain its independence, it may not welcome an interloper. But any intruder would test Enterprise's determination and allow it to revise its offer and produce a cash element.
Enterprise's difficulty is it cannot be seen to pay too much. If its bid is regarded as over-generous it could be self-defeating, damaging its own shares.
There have been suggestions it has had to work hard convincing its main institutional shareholders that its offer for Lasmo is justified.
The surging oil price is distorting the bid scene. Lasmo is a significant beneficiary of the higher crude prices.
It is likely that a US crude level nudging dollars 20 a barrel has encouraged an American group to look much more closely at the beleaguered British oil explorer. Atlantic Richfield remains the favoured US candidate.
Strengthening crude prices reflect the unease over the Korean situation and Opec's decision not to lift output.
British Petroleum rose another 3p to 411.5p, but Shell weakened 8.5p to 705.5p.
The rest of the market failed to hold an advance as New York struggled in early trading. The Bank of England's pounds 2bn gilt auction also depressed sentiment as the issue of a floating loan rate was seen as an admission of the fund- raising difficulties the Bank faces. Gilts made modest headway.
The feared option expiry turned out to be a non-event although helping turnover as final positions were covered.
After gaining 19.6 points in early trading the FT-SE 100 index ended 7.2 lower at 3,022.9.
Eurotunnel had another tough session as worries multiplied about the take-up of its controversial rights issue. The shares fell 15p to 288p and the nil-paid rights 10p to 13p.
Lucas Industries was another in the doldrums. The visits this week of analysts and fund managers to its new brake factory at Bouzonville, France, have put the shares into reverse. They started the week at 186p and closed 3p down at 175p. Societe Generale Strauss Turnbull was prompted to cut profit forecasts from pounds 70m to pounds 50m and pounds 115m to pounds 100m.
The impression that further developments are afoot in the insurance sector continued to sway sentiment. TransAtlantic was again strong, up a further 9p to 384p. The group is believed to be seeking a US acquisition.
Supermarkets found support with J Sainsbury, still enjoying Goldman Sachs backing ahead of a US investment roadshow, gaining 13.5p to 416.5p. Tesco advanced 5.5p to 229.5p.
Bowater, the paper and packaging group with a US visit set for next week, gained 5p to 459p.
Courtaulds, the chemical group, drew Smith New Court backing, although the shares failed to stir from their 504p level. The securities house is looking for 20 per cent profit growth in each of the next two years.
BTR, a Kleinwort Benson buy, gained 4p to 366p, and Caradon, the bulding materials group, dipped 11p to 300p on, it was said, a million-share overhang.
The engineer Norman Hay gained 5p to 43p following the pounds 6m sale of its 7.2-acre site near Heathrow.
International Business Communications achieved the rare feat of a bullish Friday trading statement. The shares rose 10p to 191p on a forecast that half-year profits were likely to show a 'significant advance' over last year's pounds 1.37m.
Clarke Nicholls & Coombs, a sweet maker that ventured into property, held at 9p. There is talk of a big share stake changing hands. David Kirch, the Channel Islands entrepreneur, is a big shareholder, pumping properties into the group last year.
John Mansfield, a timber group, is coming to the stock market. It will be one of the smallest full market new issues with a capitalisation of only pounds 2.5m. Stockbroker Ellis & Partners is placing shares to pay debts and for acquisitions. Based at Uttoxeter, Mansfield has five activities including supplying materials for film and TV productions. It has depots at Pinewood and Shepperton studios.
Ugland International, the shipping group born out of Bristol Channel Ship Repairers, is expected to swing into the black this year. Kleinwort Benson is looking for profits of pounds 2.5m against a pounds 1.2m loss. The group, where the Norwegian Andreas Ugland operation has 29.7 per cent, has just splashed out pounds 7.6m on two ships. More acquisitions are expected. It made a pounds 19m rights issue last year.
Shares remained dull, with one of the last accounts ending with the FT-SE 100 index down 7.2 points to 3,022.9 and the FT-SE 250 index off 7.1 at 3,527.1. Turnover was 736.8 million shares with 31,307 bargains. Settlement is due on 27 June.