Solutions to the Easter egg hunting challenge

Easter eggs in basket keyvisual

Ready for an intellectual Easter egg hunt, where we get to test you on your patent information knowledge?
Here are a number of egg-related challenges. See how many eggs you can put in your basket!

Challenge 1

We once published an article in Patent Knowledge News about eggs. When was this, and what was the article about? 

Solution to challenge 1:

Patenticulars: How do you make Japanese inside-out boiled eggs? from 14 March 2022.  

Challenge 2

Is there a classification symbol for eggs? If so, which one? 

Solution to challenge 2:

A23L 15/00 – Egg products; Preparation or treatment thereof 

Challenge 3

Find an Easter-themed device designed primarily for children, and patented by an inventor who is also the applicant. The invention, which comprises a holder and a rotating axis, makes it easier to decorate eggs with pencils, pens or paint.
Hint: the publication year is the same year as the discovery of the remains of a famous human ancestor from around 3.2 million years ago.

Solution to challenge 3:

The Lucy (Australopithecus) specimen lived around 3.2 million years ago and was discovered in 1974 in Ethiopia. 

Possible search strategies:

  • In Espacenet, search for cpc = "B44D3/low" AND pd = "1974", turn on the Filters toggle, then select only the natural persons in Applicants. Browse the 47 results to find an invention for decorating eggs.
  • In Espacenet, search with ftxt=childr* ctxt=egg? ctxt=colo?r* ctxt=rotat* 1974. Browse the 23 results to find an invention for decorating eggs.  

Challenge 4

This is the drawing of a famous chocolate egg published in a patent document in 1976. Who was the applicant? How long was the patent valid in the UK?

Patent document keyvisual 2

Solution to challenge 4:

This is the famous Kinder Surprise egg. The patent number, which also appears in the drawing, is GB1421516. The applicant was "Ferrero", and the UK patent expired after 20 years (the event GB PE20 - "PATENT EXPIRED AFTER TERMINATION OF 20 YEARS" - is shown in the Legal events view in Espacenet).  

Challenge 5

Hi, I'm an Easter bunny. It's common knowledge to us Easter Bunnies that the "0" in the C0 marker for the Unitary Patent is really an Easter egg. Well, it does look like an Easter egg, doesn't it?

What colour will the symbol for the Unitary Patent have in Espacenet and the Register?

Solution to challenge 5:

The symbol will be blue Blue icon. Visit for more details. 

Challenge 6

Find inventions for devices that separate egg yolks from egg whites.
Hint: it's always a good idea to include relevant classification symbols in your search.

Solution to challenge 6:

In Espacenet Classification search, use keywords - e.g. "egg separate yolk device" - to search for relevant CPC symbols. When you drill down on the main groups, e.g. on A47 J43/00, you'll find CPC A47J 43/14 - Devices {or machines} for opening raw eggs or separating the contents thereof.

If you search using this CPC symbol and some pertinent keywords, you'll find the relevant documents. There may be other ways to find these or similar inventions.

Challenge 7

Ever since childhood, we've known that it's the Easter bunny who lays those colourful Easter eggs and hides them for us to find. But is this fantasy or fact? Well, actually, we have proof that the Easter bunny really exists. Can you find one of these incredibly shy and rare creatures in Espacenet?
Hint: see if you can find the right subgroup for A63H 13 in Espacenet Classification search.

Solution to challenge 7:

Subgroup "03", e.g. A63H 13/03 - Egg-laying toy animals.

Espacenet Classification search 
Examples: DE334339C; GB263446A; DE389221C; DE411090C 

Challenge 8

Search in Espacenet for inventions which enable users to place "Easter eggs" on web pages.
Hint: inventors from the US and the UK came together to produce these inventions.
Hint 2: there are also Easter eggs which are neither egg-shaped nor coloured nor made of chocolate. Especially in the world of media, Easter eggs can even take on completely different meanings.

Solution to challenge 8:

Search with either this query or this query in Espacenet, to retrieve potentially relevant documents.     

Keywords: Espacenet, classification, CPC

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