Regulators are people who make sure businesses follow the rules. They are looking closely at three big companies that help people invest their money, called BlackRock, Vanguard, and State Street. These companies have a lot of power because they manage more than $23 trillion dollars for many people. Most of this money is invested in things that copy the performance of other businesses, like the S&P 500. Because these three big companies do not try to control what happens with their investments, they have less rules to follow from regulators. But now, some regulators are worried that BlackRock and Vanguard might be too involved in controlling some banks, which is not what they are supposed to do. They want to make sure these companies are following the rules and not trying to control banks with their big money. Read from source...

1. The title of the article is misleading and sensationalized, implying that regulators are targeting the big three asset managers with harsher oversight, when in reality they are just investigating whether they adhere to their passive roles in U.S. bank investments. A more accurate title could be "Regulators Review Big Three's Passive-Investing Mandate in Bank Investments".
2. The article uses vague terms such as "tighter oversight" and "strictly adhere to their passive roles", without providing any concrete evidence or examples of what these regulatory actions entail or how they would impact the big three asset managers' operations.
3. The article fails to mention the reasons why banking regulators are investigating the big three asset managers, which could be related to concerns about systemic risk, market concentration, or potential conflicts of interest. Providing this context would help readers understand the motives behind the regulator's actions and their implications for the financial industry.
4. The article does not explore the possible consequences of these investigations for the big three asset managers, such as increased compliance costs, reputational damage, or legal risks. Nor does it discuss how the big three asset managers might respond to these regulatory scrutinies, whether by changing their investment strategies, lobbying for favorable regulations, or challenging the regulator's authority in court.
5. The article ends with a paragraph that seems out of place and irrelevant to the main topic, as it lists various asset classes and services offered by Benzinga, without any connection to the story about the big three asset managers. This appears to be an attempt to promote Benzinga's products and services, which is inappropriate for a news article.

### Final answer: AI criticized the article for being misleading, vague, incomplete, and promotional.