Are Thai hospitals legally obligated to give you copies of your case records, including handwritten doctor’s notes, if you ask for them? 

They are required to give you all your records on request. However not sure that handwritten notes will still be on file. Often the files are only electronic.

 

You will have to go in person with passport to request the records.

It's been my experience that Thai hospitals will give patients their records, including handwritten doctor's notes if they exist upon request, but often there is a delay of up to a week and a charge for copying.  And they'll release electronic scan records on a CD, sometimes which can only be opened with a very old version of Windows.  I keep an ancient laptop with Windows XP for this purpose.  

 

Often the handwritten notes and some of the typed records will be in the Thai language.

 

A third party can request records if the patient gives that third party a limited power of attorney, i.e. a permission letter, with relevant details like the full name, passport number, patient number, etc.  of the patient and full name and passport details of the third party handling the request in person.

 

Edit:  if you've had dental work at the hospital and aren't interested in those records, you may wish to ask that they are excluded.  Dentists seem to make very detailed records.