How can you tell? That is the argument I have with non-commercial broadcasters and hit a brick wall. The average person listening to the radio doesn't know the difference.
For the official stuff, here are a couple of links:
https://www.fcc.gov/media/radio/nature-of-educational-broadcasting
http://www.npr.org/sections/ombudsman/2015/03/11/392355447/nprs-underwriting-guidelines-part-one
This is not bad:
https://keeppublicradiopublic.com/2010/07/27/ad-vs-underwriting/
And, finally, an article I wrote:
I add these words: Underwriting rules are vague to allow greater flexibility for stations. That flexibility hinders stations instead of helping. When stations get fined for following the rules (see Last in this article) the opposite happens. Years ago Montana had no speed limit. People got stopped and got huge tickets for things like 'unsafe driving' instead. I suspect folks in Montana welcomed a speed limit because what was legal became illegal for some other reason that was subjective, or seemingly so (a difference in opinion). The thing to remember: The FCC writes the rules and interprets them. It's hard to prove the entity that wrote the rule interpreted the rule incorrectly.
EXPLAINING UNDERWRITING WITHOUT LEGALESE
An Underwriting Credit (aka spot) should, per the advice, not rule, of the FCC, be 20 seconds or less. The FCC says the longer the spot, the better the chance you will violate rules.
A credit can include:
The name of the donor
the address, phone number, website (I have not seen an instance when a fine was issued for all three being used but see the bottom example).
a slogan, as long as it does not break the existing rules (Walmart could not use the slogan "Low Prices Every Day")
Products or services offered (be careful here and limit it to two or three...see bottom)
Brand Names (again, see "Last" below)
You cannot compare the Underwriter with others, make the Underwriter appear to be the best choice or better choice or anything else that might persuade the listener to choose that business over a competitor. You have to use your brain on wording.
Long ago a lawyer's spot said "practicing law for over 30 years from the same location". The FCC said the announcement gave the attorney an 'unfair advantage' over attorneys that had been practicing law for fewer years although it is legal to say how long the business has been operating. You'd be okay, for example, saying "First State Bank, serving the financial needs of our area since 1904". Why? An attorney is chosen based on experience, a bank is not.
Likewise, a tow truck company saying they offer 24 hour service might be fine but it would generate a fine if you add they don't charge extra for night and weekend calls. That gives them an advantage over competitors. You must ask yourself why such a statement is included. If the reason is to persuade, then you cannot say it. To say 24/7 service is informative. That you don't charge extra for nights and weekends is simply to have an unfair advantage over competitors, to persuade customers to use them for this reason.
Banks, for example, cannot say what interest they pay on CDs and such. For example they could not offer "free checking" because not every bank does. An auto repair shop cannot offer to check your tire inflation free in a credit. An insurance agency could not offer free calendars, just stop in and take one. These are designed to persuade customers to choose their business.
The official terms: No qualitative or comparative statements.
Calls of action are illegal. Here's what this means. You can give contact information but you cannot direct listeners to phone, stop by or go to a website. For example you cannot say "give them a call" or "go to the website" or "Drop by 1234 Main". You can say "the phone number is 555-1212" or "Online at www dot anybusiness dot com" You can say "offices at 1234 Main Street".
Likewise, it is illegal to say "As a thank you to KXXX listeners, you can get a 10% discount today only". This equates to pricing that is illegal and such pricing is a call to action because it is for a limited time.
You cannot say, for example, "EZ Oil and Lube, home of the 10 minute $14.95 oil change". But think harder: it is a violation to say "home of the 10 minute oil change". That one, while not price and item is competitive indicating other competitors take more than 10 minutes.
Tossing in a monkey wrench, what if the business name indicates competitive advantage: "Joe's Discount Appliances" or a home furnishings shop really named "Real Deals on Home Decor". These would be okay because if that is the legal name of the business as in their DBA, the FCC says you must identify the donor business. So, that trumps all.
You cannot be repetitive. For example, you cannot say "The phone number is 555-1212, again, that's 555-1212"
LAST: "Menu Listing". If you go to the FCC website to read the Underwriting Rules it never mentions "menu listing". WOBO got fined. Here are the credits. You will see they clearly abide by FCC Underwriting Rules, at least those that are written. However the 'unwritten' menu listing is what got them a $3,000 fine:
Birch Sheet Metal and Building Supplies in Walton, Kentucky, “featuring custom metal roofing, siding, hardware, trim, insulation, trusses, and perma felt paper.”
Fedders Feed and Seed and Pet Supplies in Covington, KY., “featuring bulk and bag mulch, peat moss, potting soil, bulk top soil and decorative borders.”
You will notice there are 7 items listed for Birch and 5 items listen for Fedders. The FCC's response is quoted:
“We find that these excessively detailed menus of multiple product/service offerings by underwriters exceed the type of information that would enable listeners to identify supporters of noncommercial programming and are similar to promotional broadcasts that have resulted in monetary forfeitures.”
One of the larger Public broadcasters, Minnesota Public Radio details what they offer:
You can use up to 40 words that may include:
1) general location of your business
2) up to three trade names, product names, or service listings
3) factual, value-neutral descriptions of products or service
4) length of time your company has been operating
5) established slogans that identify but do not promote
6) web address
How about an example:
"Support provided by Joe's Discount Appliances at 120 Main Street in Greenville, carrying Maytag, G.E. and Amana home appliances from refrigerators to blenders. "Hometown Proud", Joe's Discount Appliances, serving Greenville since 1934, online at Joe's Discount Appliances dot com."
Notes: I intentionally used "Joe's Discount Appliances" because it is the legal name of the business, the DBA, if you will. The word Discount would be a violation of FCC Rules otherwise. "Hometown Proud" might be a stab at a chain appliance store in town but Joe's has used this "Hometown Proud" in all their marketing for many, many years, therefore it is an established slogan that does not promote. While the Underwriter was mentioned more than once, it was a natural use of the name versus intentionally to be competitive (ie: to identify not promote).