We've lost count of how many times insiders have accumulated shares in a company that goes on to improve markedly. On the other hand, we'd be remiss not to mention that insider sales have been known to precede tough periods for a business. So before you buy or sell Biogen Inc. (NASDAQ:BIIB), you may well want to know whether insiders have been buying or selling.

What Is Insider Buying?

It is perfectly legal for company insiders, including board members, to buy and sell stock in a company. However, such insiders must disclose their trading activities, and not trade on inside information.

Insider transactions are not the most important thing when it comes to long-term investing. But equally, we would consider it foolish to ignore insider transactions altogether. As Peter Lynch said, 'insiders might sell their shares for any number of reasons, but they buy them for only one: they think the price will rise'.

See our latest analysis for Biogen

The Last 12 Months Of Insider Transactions At Biogen

Over the last year, we can see that the biggest insider purchase was by CEO & Director Michel Vounatsos for US$748k worth of shares, at about US$241 per share. Although we like to see insider buying, we note that this large purchase was at significantly below the recent price of US$325. Because it occurred at a lower valuation, it doesn't tell us much about whether insiders might find today's price attractive.

Biogen insiders may have bought shares in the last year, but they didn't sell any. The chart below shows insider transactions (by companies and individuals) over the last year. By clicking on the graph below, you can see the precise details of each insider transaction!

There are plenty of other companies that have insiders buying up shares. You probably do not want to miss this free list of growing companies that insiders are buying.

Does Biogen Boast High Insider Ownership?

Many investors like to check how much of a company is owned by insiders. Usually, the higher the insider ownership, the more likely it is that insiders will be incentivised to build the company for the long term. It's great to see that Biogen insiders own 0.2% of the company, worth about US$101m. I like to see this level of insider ownership, because it increases the chances that management are thinking about the best interests of shareholders.

So What Do The Biogen Insider Transactions Indicate?

There haven't been any insider transactions in the last three months -- that doesn't mean much. However, our analysis of transactions over the last year is heartening. With high insider ownership and encouraging transactions, it seems like Biogen insiders think the business has merit. In addition to knowing about insider transactions going on, it's beneficial to identify the risks facing Biogen. Every company has risks, and we've spotted 3 warning signs for Biogen you should know about.

If you would prefer to check out another company -- one with potentially superior financials -- then do not miss this free list of interesting companies, that have HIGH return on equity and low debt.

For the purposes of this article, insiders are those individuals who report their transactions to the relevant regulatory body. We currently account for open market transactions and private dispositions, but not derivative transactions.

This article by Simply Wall St is general in nature. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.

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