“Bring back the boss class, say employees fed up with self-rule” (Early editions last week, News, page 20) said in 2007 “a 28-year-old computer programmer, Brian Robertson, came up with and patented the concept of holacracy” [a self-management philosophy]. Mr Robertson was not a programmer but CEO of Ternary Software. He did not patent holacracy but trademarked it. A patent would mean that nobody could use the holacracy model without paying royalties; the trademark only restricts those who would want to sell services using the holacracy brand.

In “The heat and death toll are rising in India” (In Focus, last week, page 26), we quoted the academic Matthew Huber and said he was at Purdue Climate Change Research Center in Indiana. He is actually affiliated to the Department of Earth Sciences at the University of New Hampshire.

The May issue of Observer Tech Monthly carried a graphic outlining the gestation periods of a variety of mammals, from the tiniest to the largest. Contrary to our figures, the poor shrew does not have to wait 25 weeks to produce young; we meant 25 days. Similarly, the hamster can reproduce in 16 days – not, as we said, 16 weeks. Phew.

Write to Stephen Pritchard, Readers’ Editor, the Observer, Kings Place, 90 York Way, London N1 9GU, tel 020 3353 4656 or email reader@observer.co.uk