Shareholders in Arcon have until next Monday to accept the cash and share offer for the company from Lundin Mining. Given that the company's largest shareholder Sir Anthony O'Reilly has already pledged his 65 per cent holding, the outcome of the offer seems to be a foregone conclusion.

That said, there seems to be a considerable amount of disquiet among the 15,000 or so small shareholders who own the rest of the company, many of whose involvement dates back to Atlantic Resources which merged with Conroy Petroleum to form Arcon in 1992.

The small shareholders argument is that the price being offered by Lundin of €93 million does not square with the very bullish future painted for the company by itself and its advisers in recent months. They point to Davy Stockbrokers forecast of "bumper" pretax profits of €16.5 million for 2005 on the back of high zinc prices and a better than expected performance of the dollar versus the euro.

They also point to very upbeat comments from O'Reilly's son, the company chairman Tony O'Reilly junior, about the quality of the ore body which he describes as "the second richest in the western world".

They argue that the offer, which works out at 52.2 cent per share is at a significant discount to the 60 cent a share that Arcon was trading at in February on the back of all this positive sentiment. Lundin claim in their offer document that the offer actually represents a 14 per cent premium on the price of 46 cent the shares had fallen to prior to the posting of the document in mid-March.

They also argue that it's at a significant premium to the average price over the three months leading to the announcement of the offer.

The reason for the fall in Arcon's share price since the announcement of the offer is not immediately obvious and not fully explained by changes in the zinc price or the exchange rate trends propelling the share price in February. Undoubtedly the decision of some shareholders to sell into the market now because they don't want Lundin shares is also a factor.

But before one can conclude Lundin is getting a bargain, you have to ask why O'Reilly - who is not known for leaving money on the table - would accept such an offer. In order to answer that you have to get a handle on how well or badly O'Reilly is doing, which is difficult given that his involvement in the company goes back to the 1980s and he has participated in numerous fundraisings.

His representatives say that his investment in the group since its creation in the 1992 merger of Atlantic Resources and Conroy is something in the region of €60 million when exchange rates and other factors are taken into account. This leaves him pretty much washing his face on the basis of the €58 million valuation put on his 111 million shares by the offer. Arguably, most of the other shareholders are in the same boat post the Lundin offer, which is not a bad outcome all things considered.

But dissidents claim O'Reilly has probably done better than the majority of shareholders as he acquired a large portion of his shares at the equivalent of 30 cents a share in a rights issue two years ago, which saw his stake increase from around 40 per cent to its current level. Small shareholders claim that shares bought at these levels in the rights issue make up a much smaller portion of their shareholding, and thus their gains are smaller.

They also argue there are a number of other features of the offer which are uniquely attractive to O'Reilly.

Under the terms of the deal he will be released from his position as guarantor of a €6.6 million mine closure bond. He is also owed something in the region of €18.5 million by Arcon as a result of the 2002 refinancing, which will be repaid as part of the takeover. His family's interest in the company will continue to be represented at board level as Tony O'Reilly junior is due to join the Lundin board after the merger.

Another attraction for O'Reilly is that merger will free up something in the region of €30 million in cash that was tied up in an illiquid investment. O'Reilly will have plenty of uses for this money, of which administering a coup de grace to Waterford Wedgwood's existence as a quoted company must be one possibility.

When you take all of this into account, the small shareholders in Arcon would appear to have something to be less than gruntled about. But at the same time they have to acknowledge that all of this information has been disclosed in the prospectus and the takeover panel has given it the all clear.

The panel also approved the composition of a committee of independent directors that recommended the offer on the basis that it diversified the risk inherent in a company that's major asset is a single mine with a five-year lifespan. Arcon shareholders will retain an interest in the 12th largest zinc producer.

There is also another argument that has to be heard, which is that O'Reilly stepped up in 2002 and underwrote the rescue of the company - albeit on the best possible terms he could - and that he is entitled to reap his reward when the opportunity presents itself as long as no laws are broken.

That is one of the unwritten rules of the market. Another is that small shareholders always seem to be the losers.