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LV426

macrumors 68000
Jan 22, 2013
1,835
2,262
Just to be "that guy"...

While people often do refer to this as a "digital signature", it really isn't anything of the sort. A digital signature is a cryptographic entity that at some level proves that you are indeed who you claim you are. It generally doesn't involve anything resembling your on-paper signature.

Anyone can append a rasterized/digitized version of your written signature to a document - it doesn't have to be you. With a real digital signature, though, that can't happen unless you are sloppy with your private key(s).

Well said, 'that guy'.

On my nasty Windows PC at work, I use Adobe Reader to view PDFs. In that program, I have the ability to properly 'sign' a document with a certificate (these are available from various sources). Recipients of my documents then know for sure that it was me, and only me, that signed the document, not some fool who has the simple ability of adding a signature image scan.

I emailed Apple about this already. Since every user has an Apple ID, it would be dead easy for Apple apps (Preview, Pages, Numbers etc.) to have the facility to sign documents properly on demand, using your Apple ID. It's a real shame that feature isn't there already.
 

madrag

macrumors 6502
Nov 2, 2007
371
92
This is exactly what I was going to say. I thought this article would be about RSA.
Me three!

This scanned signature is a joke, if I sent my invoices with such a signature, my clients would laugh (and obviously return it), this has no legal value whatsoever.

I was hoping to view an easy way to sign with a certified signature (a cryptographic token) in Preview.app, I've been doing it with Acrobat until now.
 

Claudius2k

macrumors newbie
May 14, 2009
26
3
Quit whining. Nobody is asking you to pay for it. It's free in OS X.

Thank you. I like this tip.
 

Infinitewisdom

macrumors 6502a
Sep 23, 2012
775
567
Nice awareness-raising article but I am not sure why this is a Macrumors post. I've been signing PDFs on my 2013 mba for a while now so it isn't a brand new thing. Maybe new to Yoshemite though.

Yes you can import images. Just drag and drop the signature image file onto the PDF. You might need to be in signature mode first, I can't remember.

It's not new to Yosemite is it? I've been doing this in Preview for a while too.
 

RedTomato

macrumors 601
Mar 4, 2005
4,155
442
.. London ..
No, a PDF in Preview will not allow you to import/drop an image into it. The PDF has to be converted to an image, then you drop the image into it and convert back to PDF.

If you believe this to be wrong perhaps you could create some step by step instructions, because my own testing and a whole lot of googling and no one else has found out how to do this.

Ah, I was wrong re drag & drop images onto PDF. Turned out the PDF on which I did this, I saved as a JPEG or something, then dropped my signature file on it, and resaved as a PDF. Lol.

Also been known to copy and paste text from a page of a PDF to a Word doc (it keeps most of the formatting) for altering / inserting something, then re-save as PDF, and re-insert the relevant page via Preview.

----------

Me three!

This scanned signature is a joke, if I sent my invoices with such a signature, my clients would laugh (and obviously return it), this has no legal value whatsoever.

I was hoping to view an easy way to sign with a certified signature (a cryptographic token) in Preview.app, I've been doing it with Acrobat until now.

I understand what you mean. However I'm frequently emailed files / contracts / agreements and asked to print, sign, scan and return them. This saves all that printing and scanning hassle.

I've never in my life been asked to cryptographically sign a document. I'm sure the day will come, it hasn't arrived yet.
 

-LikesMac-

macrumors 6502
Jun 20, 2010
429
23
Well this is out of the blue...

I remember this feature. It was introduced in Mac OS X Lion. I recall checking out the feature the first day I updated to Lion. It's been years.

Also, it's unfortunate that this is referred to as "digitally signing" the PDF, since that in actuality means something quite different as others have mentioned.
 

aquajet

macrumors 68020
Feb 12, 2005
2,386
9
VA
Just to be "that guy"...

You should not feel bad about this. A digital signature is something very different than what is described in this article. If someone is researching how to digitally sign a document on a Mac and comes across this article, the information provided is entirely wrong and misleading. I have submitted a report of the original post asking that the terminology be changed.
 

C DM

macrumors Sandy Bridge
Oct 17, 2011
51,390
19,458
You should not feel bad about this. A digital signature is something very different than what is described in this article. If someone is researching how to digitally sign a document on a Mac and comes across this article, the information provided is entirely wrong and misleading. I have submitted a report of the original post asking that the terminology be changed.
Changed to what exactly, out of curiosity?
 

aquajet

macrumors 68020
Feb 12, 2005
2,386
9
VA
Well said, 'that guy'.

On my nasty Windows PC at work, I use Adobe Reader to view PDFs. In that program, I have the ability to properly 'sign' a document with a certificate (these are available from various sources). Recipients of my documents then know for sure that it was me, and only me, that signed the document, not some fool who has the simple ability of adding a signature image scan.

I emailed Apple about this already. Since every user has an Apple ID, it would be dead easy for Apple apps (Preview, Pages, Numbers etc.) to have the facility to sign documents properly on demand, using your Apple ID. It's a real shame that feature isn't there already.

Except that a cryptographic public/private key pair would have to also be associated with an Apple ID in order to meet the basic requirements of integrity, authenticity and non-repudiation of a document. Apple could probably devise a relatively easy to use system, but in order for it to be trustworthy a user would have to have some knowledge of key management in such a scheme. At that point you are already assuming a certain level of technical knowledge, certainly something I wouldn't consider "dead easy". ;-)
 

LV426

macrumors 68000
Jan 22, 2013
1,835
2,262
Except that a cryptographic public/private key pair would have to also be associated with an Apple ID in order to meet the basic requirements of integrity, authenticity and non-repudiation of a document. Apple could probably devise a relatively easy to use system, but in order for it to be trustworthy a user would have to have some knowledge of key management in such a scheme. At that point you are already assuming a certain level of technical knowledge, certainly something I wouldn't consider "dead easy". ;-)

1. User edits a document
2. User clicks File | Sign
3. Choose to use your Apple ID or a certificate of your choice. Let's say Apple ID.
4. User is prompted to enter the password for his Apple ID
5. Document is signed digitally

I doubt you could get much simpler than that, and requires very little technical knowledge! An Apple-generated certificate would be used behind the scenes.
A recipient of a PDF or iDocument would be able to see a verifiable digital signature:
'Digitally signed by Apple Inc. for joe.bloggs@icloud.com'
 

C DM

macrumors Sandy Bridge
Oct 17, 2011
51,390
19,458
This is more about an actual personal human signature that goes on basically printed documents. It doesn't matter if some actual digital signature with certificate and whatnot is used when documents are meant to have a human personal signature on them for all kinds of reasons, usually various legal ones.

When and if that changes as far as how society works with papers of importance essentially then the whole digital part (as it's truly meant) could apply in general. But as the article mentions, this is basically just electronically signing an equivalent of a paper document (not really talking about digitally signing something).
 
Last edited:

doctor-don

macrumors 68000
Dec 26, 2008
1,604
336
Georgia USA
In my current version of Mavericks, I have to use the menu to View > Show Edit Toobar. No Toolbox is visible / available.

Were YOU, the author, referring to Preview in Yosemite?
 

wilsonlaidlaw

macrumors 6502
Oct 29, 2008
443
74
Preview simpler than Acrobat Pro for signature

At least Preview makes it simpler than Acrobat Pro 10. I had to fill in a pre-prepared PDF form today, which I did in Acrobat 10 Pro. What a heave and then Acrobat 10 makes it really laborious to insert a scanned signature. You just used to be able to cut and paste, then move the signature to where you wanted it and accept but you now have to first save a copy of the PDF, open the copy, then go into tools/edit object, click where you want the object and then import the signature file, finally moving it and resizing to correct size. Why do programmers over-complicate things?
 

JMon14

macrumors newbie
Oct 6, 2015
1
0
Preview simpler than Acrobat Pro for signature

At least Preview makes it simpler than Acrobat Pro 10. I had to fill in a pre-prepared PDF form today, which I did in Acrobat 10 Pro. What a heave and then Acrobat 10 makes it really laborious to insert a scanned signature. You just used to be able to cut and paste, then move the signature to where you wanted it and accept but you now have to first save a copy of the PDF, open the copy, then go into tools/edit object, click where you want the object and then import the signature file, finally moving it and resizing to correct size. Why do programmers over-complicate things?

So I know I have made this more complicated than it needs to be but...once you are done writing your first name with the track pad, how do you stop the ink and restart to sign last name?
 

wilsonlaidlaw

macrumors 6502
Oct 29, 2008
443
74
So I know I have made this more complicated than it needs to be but...once you are done writing your first name with the track pad, how do you stop the ink and restart to sign last name?
I didn't. I scanned in a written signature in ink with a flat bed scanner as a JPEG and store various sizes of this in my Pictures folder. I have tried doing what you suggest with a Wacom Intuos 4 tablet, gave up and went to a scanned JPEG. Lifting the Wacom pen off is supposed to stop the ink flow but the end result looked nothing like my real signature.
 

Chloec

macrumors member
Nov 27, 2014
59
13
Actually, my macbook air's Preview is unable to sign a PDF, the version is too lower, but i don't want to update the system now. Therefore, use this application to replace. Many signature applications in the internet, some need to purchase, however there is free one could do the trick, use mouse to sign a PDF and export it.
 

Mikenng

macrumors newbie
Sep 12, 2017
1
0
Actually, my macbook air's Preview is unable to sign a PDF, the version is too lower, but i don't want to update the system now. Therefore, use this application to replace. Many signature applications in the internet, some need to purchase, however there is free one could do the trick, use mouse to sign a PDF and export it.

The best solution is indeed, Preview... It's built into Mac OSX and is the easiest to use if you want to create/edit/view PDF files.

Thanks Apple for thinking this through! :)
 

Marx55

macrumors 68000
Jan 1, 2005
1,915
753
Shocking… Really shocking… That is not an electronic signature at all. That is a copy/paste of a picture showing a handwritten signature. Anyone could do it just forging or scanning such signature. Its legal validity is zero. A true electronic signature is a certified signature (a cryptographic token), as can be done with Adobe Acrobat Pro DC. Just about time that Apple implemented that in Preview as well.
 

Peter43

macrumors newbie
Apr 2, 2019
1
1
Ok, for those who don't have a trackpad, and who also think the camera "scanned" signature looks crappy:
Open up a random PDF in the Mail app on your iPhone or iPad, press the mark up icon on the top left, then the + icon on the bottom right, then signature. Create your signature here. It is then synced to all of your devices for use.
 
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