Who inside Northern Trust Corporation (LSE:0K91) is buying or selling its shares, how big the trades are, what each insider still holds, and how the stock moved after their earlier trades, all taken from official filings.

Insider transaction

A purchase or sale of a company's shares by its directors, officers or major shareholders, taken from the official filing (in the US, SEC Form 4, due within two business days of the trade).

Open-market purchase

An insider buying shares on the market with their own money, as opposed to receiving them through options, awards or compensation plans. It is the transaction type most read as a signal of conviction.

Cluster buy

Several insiders of the same company buying within a short window of each other.

Insider track record

How a company's share price moved in the months after a given insider's past trades: whether that person's buying and selling has historically been well timed.

Source: ORTEX. Some figures are limited on the free view; live data and full history are part of ORTEX Advanced.