At lunchtime AEDT on Thursday, the benchmark S&P/ASX200 index was up 42.8 points, or 0.51 per cent, to 8,449.5, while the broader All Ordinaries
The ASX200 was set to break Monday's record close of 8,417.6 as its best finish ever, and was just 12.6 points from its intraday record high, also set that day.
Every sector was in the green except for consumer discretionaries, which was marginally lower despite a huge jump for AVJennings.
The home builder had soared 87.9 per cent to a six-year high of 62 cents after receiving a takeover offer from Proprium Capital Partners to take the company private at 67 cents per share.
AVJennings' board said it would unanimously recommend shareholders accept the offer once it is finalised.
Health care was the biggest gainer, rising 1.4 per cent as CSL added 1.5 per cent and Sigma Health Care climbed 6.5 per cent.
In the financial sector, IAG was up 4.3 per cent to $8.53 after the insurance giant said it entered into a 25-year deal with the Royal Automobile Club of Queensland to provide insurance products to RACQ members.
All of the big four banks were higher, with CBA up 1.1 per cent, Westpac gaining 1.2 per cent, NAB rising 1.3 per cent and ANZ adding 0.5 per cent.
In the heavyweight mining sector, BHP had grown 0.7 per cent, Fortescue had climbed 0.4 per cent while Rio Tinto had dipped 0.4 per cent.
The Australian dollar was buying 65.04 US cents, from 64.75 US cents at Wednesday's ASX close.