Stephen Foley: Lawyers fight it out with directors, and never mind the shareholders

US Outlook: As the late Steve Jobs faced up to his diagnosis of cancer and tried to face down the disease, he reached for the highest of hi-tech measures: he sequenced his entire DNA.

Our genetic make-up holds clues that can help us to understand the risks and the development of our diseases – cancer in particular, it seems – and therefore can help doctors to choose the drugs that have the best shot at working. It could not save the founder of Apple, but it has helped to shrink the tumours and lengthen the lives of many others.

The Apple founder was so optimistic about the technology, he told his biographer that he would be the first person to outrun pancreatic cancer, or among the last to die from it. But Mr Jobs was a visionary, always ahead of his time.

Desperate cancer patients of considerably less means than Mr Jobs are paying out of pocket to have their genes sequenced. Companies such as 23andme –which gets a lot of publicity because its founder is Anne Wojcicki, wife of Google founder Sergey Brin – are trying to popularise genetic testing for people interested in their ancestry as well as their health. The technology is getting closer and closer to the doctor's surgery, and private health insurers in the US are under increasing pressure to fund more uses for gene sequencing.

So you didn't need to be a Jobsian visionary to foresee a takeover battle for the San Diego gene sequencing company Illumina. That battle finally broke out this week, when Roche, the Swiss pharmaceuticals giant, launched a $5.7bn hostile bid for the company.

I wouldn't expect a quick resolution to this one. Illumina hasn't just rejected the offer, it has also installed a poison pill defence so that any stakebuilding by Roche will be offset by the issue of massive amounts of new stock. Outrageous as they may be, poison pills are still legal in the US.

On the other side, class action lawyers are rounding up shareholders for a legal action against the Illumina board, accusing directors of self-servingly rejecting a premium offer just so they can keep their jobs. Yes, this the US: it's directors vs lawyers, and sod what the shareholder wants.

Illumina shareholders have been wobbling on their commitment to the company. For the moment, the bulk of its business is selling machines and associated supplies to universities and research hospitals, since the bulk of sequencing work is still at the research level rather than for personal diagnostics. That will change in time, but until then the company is suffering from the squeeze on budgets in the public sector.

That is why Severin Schwan, Roche's chief executive, has pounced now. Roche and Illumina are ideal partners for the long run. Roche has been a pioneer in personalised medicine, because it has both a drug development and a diagnostic testing business. As the maker of some of the world's most successful cancer drugs, including Avastin and Herceptin, it has more expertise on this subject than any company, while its diagnostics division has the salesforce to push future generations of Illumina products. In other words, it can afford more than the 18 per cent premium it is offering to Illumina's depressed December share price.

Mr Schwan should pay up. That is what a visionary would do.