AdvertisementWASHINGTON — The federal government is stepping up its scrutiny of the world’s biggest tech companies, leaving them vulnerable to new rules and federal lawsuits. Regulators are divvying up antitrust oversight of the Silicon Valley giants and lawmakers are investigating whether they have stifled competition and hurt consumers.After a spate of unusual negotiations, the Justice Department has agreed to handle potential investigations related to Apple and Google, while the Federal Trade Commission will take on Facebook and Amazon.Lawmakers in the House said on Monday that they were...…AdvertisementWASHINGTON — The federal government is stepping up its scrutiny of the world’s biggest tech companies, leaving them vulnerable to new rules and federal lawsuits. Regulators are divvying up antitrust oversight of the Silicon Valley giants and lawmakers are investigating whether they have stifled competition and hurt consumers.After a spate of unusual negotiations, the Justice Department has agreed to handle potential investigations related to Apple and Google, while the Federal Trade Commission will take on Facebook and Amazon.Lawmakers in the House said on Monday that they were...WW…