Month: September 2025

When it comes to my ongoing project, The Great MicroSD Card Survey, I’ve been categorizing my cards into one of three groups:

• Name brand cards
• Off-brand cards
• Knockoff cards

The intent was that on-brand cards would be those cards that came from well-known, reputable manufacturers; off-brand cards would be those cards that came from less well-known manufacturers; and knockoff cards would be those cards that were trying to impersonate another more well-known brand.

The problem is that I didn’t have an objective set of criteria to use to determine what is an on-brand card, what’s an off-brand card, and what’s a knockoff card — up until now, I’ve been making that decision mainly based on vibes.

So here’s my attempt to fix that.

Here’s the criteria that I’ve come up with (including some of my notes as to why I included that criteria):

A card shall be considered a name-brand card if all of the following are true:

• Either of the following are true:
  • The card comes in a retail package that identifies the vendor who is selling the card, including the vendor’s name, mailing address, phone number, and support contact information.
    • (Pretty much all of the fake flash that I’ve been buying, as well as several off-brand cards, have come in generic packaging that doesn’t include any information on who made it, where to get support, disclosures on things like size claims, etc. This is designed to weed out those cards.)
  • The card did not come in a retail package, but the vendor or manufacturer can be identified through the manufacturer ID and OEM ID programmed into the card’s CID register.
    • (The SanDisk Industrial 8GB’s I bought came in loose packaging — and I believe that’s because SanDisk doesn’t sell them in less than case quantities. I think I bought them from a vendor that split up a case and sold them individually.)
• The vendor owns or significantly controls the brand name that appears on the card.
  • (This is designed to weed out cards where the vendor just licensed another name-brand — like HP and Kodak.)
• The vendor sells more than just SD cards and microSD/TransFlash cards.
  • (A lot of off-brand cards have brand names that only appear on microSD cards; this is designed to weed those out)
• The brand name is not known to be a private-label brand.
  • (This is designed to weed out private label cards like Amazon Basics, Micro Center, and onn.)
• The vendor has a website that shows the products that they sell.
  • (A lot of off-brands don’t even have a website; this is designed to weed those out.)
• The card is not fake flash, and no other cards from the same brand have been observed to be fake flash.
  • (Reputable name brands don’t sell fake flash. If you’re selling fake flash, you don’t get to be considered a name-brand card.)
• The information in the card’s CID register does not bear any signs that the vendor or manufacturer was attempting to conceal the card’s true origin. These signs shall include (but are not limited to):
  • Manufacturer ID field being set to hex 00 or hex fe
    • (The SD Association is responsible for assigning these values — and I don’t honestly believe that they’ve ever assigned these values to anyone.)
  • OEM ID field being set to hex 0000 or 3432
    • (Again, the SD Association is responsible for assigning these values — and I don’t believe they’ve assigned these values to anyone.)
  • Product name field being set to a string indicating that no consideration was given to its value — such as 00000, asdfg, SDABC, CBADS, a string consisting of all spaces, a string that contains characters outside the range of 32-126, etc.
    • (I’ve only ever seen this happen with fake flash and off-brand/knockoff flash. A legitimate manufacturer shouldn’t be using generic values like these.)
  • Serial number being set to hex 00000000.
    • (Yes, I have cards in my collection where they set the serial number to all zeroes.)
  • The same serial number being observed on different cards of the same model and size.
    • (Yes, I have cards in my collection where they used the same serial number across multiple cards.)

A card shall be considered a knockoff card if any of the following are true:

• The card bears a well-known brand name, and any of the following are true:
  • The package does not identify the vendor’s name, address, phone number, or support contact information.
    • (A lot of knockoffs come in generic packaging that doesn’t identify who made it or where to get support — for obvious reasons.)
  • The card is fake flash.
    • (Reputable vendors don’t sell fake flash.)
  • No evidence exists indicating that the product was manufactured by, sold by, sanctioned by, or made under license from, the owner of the name brand.
    • (Designed to be kind of a catch-all.)
• The brand name is substantially similar to a well-known name brand.
  • (This is designed to catch brands like Sansumg, SanDian, Amzwn, etc. — where a consumer could reasonably miss the difference in spelling and end up buying it thinking it was a name-brand card.)
• The brand’s logo uses visual elements that are substantially similar to those used by a well-known name brand.
  • (Again, this is designed to catch instances where a consumer might see those visual elements and reasonably get confused into thinking that they’re buying a name-brand card. For example, Sansumg copied Samsung’s logo, but swapped around the N and M; SanDian used the stylized “nD” from SanDisk’s logo; and Amzwn used Amazon’s “A to Z” arrow.)

A card shall be considered an off-brand card if it cannot be determined to be a name-brand card or a knockoff card.

I’d love to make this an open discussion — so let me know in the comments what you think of this!