The alternative to this being what? Say there is a lock-in period for insiders and the company’s future earnings are hit hard. Since the insiders cannot cash in before the fall in share value, they have every incentive to cook the books and engage in fraudulent accounting (think Enron) in order to maintain the share value. And they’ll eventually bail, making the shareholders take the loss. Anyone with such inside information has a great incentive to take advantage of it. It just cannot be prevented.
The fall out of this would be a cry for greater regulation of financial markets, causing more distortions in the market mechanisms.
In the long run, this would hurt both the “good” companies and the capital markets itself.
You might argue that the penalty for corporate fraud would be so high that it just won’t be done, that companies would be transparent in reporting their losses. If that’s the case, why should there be restrictions on inside trading at all? The markets would be better served by mandatory disclosures of share sales of the insiders.
This is speculation. And almost all market participants are speculators. And information is always at a premium. Information asymmetry cannot be vanquished by the wave of a regulatory wand.
What if the insider was wrong in his assessment of the information? What if the public benefited by offloading their shares to him at a higher price? That’s the risk the insider takes, for which he is compensated. Much the same way, the public takes the risk with regard to non-public information.
Assessments of risks are always subjective. Risk premiums are set by different investors using different models. They keep evolving. They even take into account different types of risks and weigh them differently. The only answer to that would be: it depends.
But they do pay for information. They spend time gathering that information. And friends and family build goodwill with the insider in order to gain that information. Nothing is free.
And lastly, there are such things as private contracts which the employee can sign, which will limit their ability to indulge in such transactions. If a company has a record for such shady dealings, it will not be able to attract investors who do their homework well. Reputation matters. Regulations do nothing but waste taxpayer’s money on regulatory agencies, drain the wealth of companies faced with litigation costs and lawyer fees and do nothing to help the average investor. If a company does not go bankrupt due to its losses, it surely will after meeting these additional costs. Its a scenario where everyone loses, except the lawyers.