A regulator's crackdown on National Australia Bank and three casino operators has shareholders worried about what penalties may be coming.
The Australian Transaction Reports and Analysis Centre (AUSTRAC) found serious problems in how the bank, Crown Resorts, SkyCity and Star Entertainment try to prevent financial crimes.
The watchdog ruled out fines for NAB, but could force wide-ranging changes to how the companies operate.
Investors sold each of the four companies lower on the market on Monday.
The biggest, NAB, fell 3.16 per cent to $26.64.
Financial shares dropped more than one per cent and were the difference between gains and losses for the market.
The benchmark S&P/ASX200 index closed down 13.5 points, or 0.19 per cent, to 7281.9.
The All Ordinaries closed lower by 11.7 points, or 0.16 per cent, to 7531.6.
Major shares categories such as materials and energy were little changed.
The big miners were mixed.
BHP and Rio Tinto gained less than one per cent. Fortescue dropped 1.39 per cent to $22.65.
Information technology shares were the standout and rose 2.8 per cent.
Electronics design software vendor Altium jumped 39.03 per cent to $37.83.
Altium's board rejected a takeover offer from US software group Autodesk of $38.50 per share.
Artificial intelligence provider Appen gained 6.13 per cent to $12.99.
The troubles for the three casino operators caused shares in consumer discretionaries to fall 0.89 per cent.
AUSTRAC widened its investigation into Crown Resorts to include its Perth casino.
Shares were down 1.5 per cent to $12.50.
Sydney casino operator Star Entertainment was told it also has potentially serious problems with its anti-money laundering efforts.
Shares were down by 2.02 per cent to $3.89.
Adelaide casino operator SkyCity Entertainment fielded similar concerns.
Shares were lower by 6.47 per cent to $3.18.
Elsewhere on the market, engineering group CIMIC responded to media reports about a possible share market listing for services provider Ventia.
CIMIC has a 47 per cent stake in Ventia and said a share market listing was one option being considered.
CIMIC shares were up 1.34 per cent to $21.34.
Overseas, there has been little response on futures markets to the G7's agreement on a minimum global corporate tax rate of at least 15 per cent.
The pact is aimed at getting US tech giants to pay more tax.
The Nasdaq and S&P 500 futures have been little changed.
US markets provided a good lead on Friday after weak jobs data eased investors' concerns of inflation.
On Tuesday, the weekly ANZ-Roy Morgan consumer confidence index is published.
Melbourne's extended coronavirus lockdown could take a toll.
The National Australia Bank's monthly business survey for May is also due after setting record highs for both conditions and confidence in April.
The Australian dollar was buying 77.39 US cents at 1730 AEST, higher from 76.61 US cents at Friday's close.
ON THE ASX
* The benchmark S&P/ASX200 index closed down 13.5 points, or 0.19 per cent, to 7281.9 on Monday.
* The All Ordinaries closed lower by 11.7 points, or 0.16 per cent, to 7531.6.
* At 1730 AEST, the SPI200 futures index was trading even at 7281.
One Australian dollar buys:
* 77.39 US cents, from 76.68 cents on Friday
* 84.77 Japanese yen, from 84.47 yen
* 63.66 Euro cents, from 63.30 cents
* 54.75 British pence, from 54.35 pence
* 107.43 NZ cents, from 107.16 cents.