It's legal, but it doesn't matter, and won't affect the person's job.
you can inform me
The abstract noun forms of the verb to 'inform' are information and the gerund, informing.
A former employer may inform a prospective employer at his discretion.
Not at all, if the former employer was disatisfied they have every right to inform future employer, if asked.
Yes
An employer can enforce an arrest, but they should really inform Law Enforcement to arrest you.
Yes, you must inform your employer 30 days before you enter drug rehab. Your employer will then determine whom to hire or relocate to replace you when you are gone.
your supervisor or manager are the best persons to report to.
An employer has a duty to inform the employee of an changes to the employment terms. If an employer is out on workers' compensation, and they are terminated, the employer has a duty to communicate that information to the employee and pay that employee any money they have due to them.
They must notify you of your COBRA rights.
W-4
No but you need to inform DEFRA if you keep livestock.