The phrase 'complicated rules' is correct and usable in written English. You can use it to refer to rules or regulations that are complex or difficult to understand. For example: "The department has a set of complicated rules that must be followed to the letter.".
Because more government breeds complicated rules and laws that a small business can't afford to follow.
The agency uses complicated rules to settle which beneficiaries receive how much additional coverage.
Buying a home overseas requires navigating what are often complicated rules on foreign ownership.
It has been known as an audit trap, in part because complicated rules have resulted in filing errors.
At the time, chip designs followed complicated rules and were painstakingly patterned by hand on Mylar sheets.
He said the loophole showed the "over-complicated" rules around claiming benefits.
Straightforward rules save people from decision fatigue, whereas complicated rules intensify it.
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